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Rocket stove. Camping rocket stove drawings. DIY rocket stove. Drawings

Let's say right away: rocket stove - a simple and convenient heating and cooking device using wood fuel with good but not exceptional parameters. Its popularity is explained not only by its catchy name, but moreover by the fact that it can be made with one’s own hands and not by a stove maker or even a mason; if necessary - literally in 15-20 minutes. And also because, by investing a little more work, you can get an excellent bed in your home without resorting to complex, expensive and bulky construction. Moreover, the very principle of the design of the rocket stove gives greater freedom to design and the manifestation of creative abilities, see fig.

But what is perhaps more remarkable is the “jet furnace” for the huge number of, at times, completely absurd inventions associated with it. Here, for example, are a few pearls snatched at random:

“The principle of operation of the furnace is the same as that of the MIG-25 ramjet engine.” Yes, the MIG-25 and its descendant MIG-31 did not even sit down in the bushes near the ramjet engine (ramjet engine), as they say. The 25th and 31st are powered by double-circuit turbojet engines (turbojet engines), four of which later pulled the Tu-144 and still power other vehicles. And any stove with any jet engine (RE) is technical antipodes, see below.
“Reverse jet thrust furnace.” Is the stove flying tail first, or what?
“How will she blow out such a pipe?” A non-pressurized oven does not blow into the chimney. On the contrary, the chimney draws from it, using natural draft. The higher the pipe, the better the pull.
“The rocket stove is a combination of a Dutch bell stove (sic!) with a Russian stove bench.” Firstly, there is a contradiction in the definition: a Dutch oven is a channel oven, and any bell-type oven is anything but a Dutch oven. Secondly, the bed of a Russian stove warms up completely differently than a rocket stove.

Note: in fact, the rocket stove was so nicknamed because in the wrong combustion mode (more on that later), it makes a loud whistling hum. A properly tuned rocket stove whispers or rustles.

These and similar inconsistencies, understandably, confuse and prevent you from making a rocket stove properly. So let's figure out what the truth is about the rocket stove, and how to use this truth correctly so that it really good stove showed all her strengths.

Furnace or rocket?

For complete clarity, we still need to figure out why a stove cannot be a rocket, and a rocket cannot be a stove. Any RD is the same as an internal combustion engine, only the escaping gases themselves act as pistons, connecting rods with a crank and transmission. In a piston internal combustion engine, already at the moment of combustion, the high temperature of the working fluid creates a lot of pressure, which pushes the piston, and it moves all the mechanics. The movement of the piston is active, the working fluid pushes it to where it itself tends to expand.

When fuel is burned in the combustion chamber of the thruster, the thermal potential energy of the working fluid is immediately converted into kinetic energy, like that of a load falling from a height: since the outlet for hot gases is open to the nozzle, they rush there. In the RD, the pressure plays a subordinate role and nowhere exceeds the first tens of atmospheres; this, for any conceivable nozzle cross-section, is not enough to accelerate the migar to 2.5 M or launch a satellite into orbit. According to the law of conservation of momentum (amount of motion), the aircraft with a taxiway receives a push in the opposite direction (recoil impulse), this is jet thrust, i.e. thrust from recoil, reaction. In a turbofan engine, the second circuit creates an invisible air shell around the jet stream. As a result, the recoil impulse is, as it were, contracted in the direction of the thrust vector, so a turbofan engine is much more economical than a simple turbofan engine.

In a furnace there is no conversion of energy types into each other, therefore it is not an engine. The stove simply distributes potential thermal energy appropriately in space and time. From the point of view of the furnace, an ideal RD has an efficiency = 0%, because it only pulls due to fuel. From the point of view of the jet engine, the stove has an efficiency of 0%, it only dissipates heat and does not draw at all. On the contrary, if the pressure in the chimney rises to or above atmospheric pressure (and without this, where will the jet thrust or active force come from?), the stove will at least smoke, or even poison the residents or start a fire. The draft in the chimney is without pressurization, i.e. without external energy consumption, it is ensured due to the temperature difference along its height. Potential energy here, again, is not converted into any other energy.

Note: in a rocket thruster, fuel and oxidizer are supplied to the combustion chamber from the tanks, or they are immediately refueled into it if the thruster is powered by solid fuel. In a turbojet engine (TRE), the oxidizer - atmospheric air - is pumped into the combustion chamber by a compressor driven by a turbine in the exhaust gas flow, the rotation of which consumes some of the energy of the jet stream. In a turboprop engine (TVD), the turbine is designed so that it selects 80-90% of the jet power, which is transmitted to the propeller and compressor. In a ramjet engine (ramjet), the air supply to the combustion chamber is ensured by hypersonic speed pressure. A lot of experiments have been carried out on ramjet engines, but there have been no production aircraft with them, there are none, and there are no plans to do so, as ramjet engines are too capricious and unreliable.

Kan or not Kan?

Among the myths about the rocket stove, there are some that are not entirely absurd, and even somewhat justified. One of these misconceptions is the identification of the “racket” with the Chinese kan.

The author had the opportunity to visit the Amur region in winter, in the Blagoveshchensk region, as a child. Even then there were a lot of Chinese living in the villages there, fleeing in all directions from the cultural revolution of the Great Chairman Mao and his completely frostbitten Red Guards.

Winter in those parts is not like Moscow, frost of -40 is common. And what amazed and aroused interest in stoves in general was how Chinese fanzas were heated by canals. Firewood is transported to Russian villages by carts, and smoke comes out of the chimneys in a column. And all the same, in a hut made of logs not the size of a child’s girth, by morning the corners from the inside were frozen. And the fanza is built like a country house (see picture), the windows are covered with fish bladder or even rice paper, bunches of wood chips or twigs are placed in the can, but the room is always warm.

However, there are no subtle thermal engineering wisdom in the can. This is an ordinary one, only small, kitchen stove with a lower exit into the chimney, and most of the chimney itself is a long horizontal channel, a hog, on which a bench is located. The chimney, for fire safety reasons, is outside the building.

The effectiveness of the can is determined primarily by the thermal curtain it creates: the couch goes around, if not the entire perimeter from the inside, except for the door, then certainly 3 walls. Which once again confirms: the design and parameters of the stove must be linked to those of the heated room.

Note: The Korean Ondol stove operates on the principle of a warm floor - a very low stove occupies almost the entire area of the room.

Secondly, in the very cold, the Kans were drowned with argal - the dried droppings of ruminant animals, domestic and wild. Its calorific value is quite high, but argal burns slowly. In fact, an argal fire is already a long-burning stove.

It is not the Russian custom to constantly stick twigs into the oven, and our men disdained to cook food in cattle feces. But travelers of the past highly valued argal as a fuel; they collected it along the way and took it with them, carefully protecting it from getting wet. N. M. Przhevalsky in one of his letters stated that without argal he would not have been able to conduct his expeditions in Central Asia without losses. And the British, who disdained argal, had 1/3-1/4 of the detachments’ personnel returning to base. True, he was recruited from sepoys, Indian soldiers in English service, and pandits - spies recruited from the local population. One way or another, the highlight of the rocket stove is not at all the bed on the hog. To get to it, you will have to learn to think like an American: all the primary sources on the rocket furnace are from there, and utter speculation is generated only and only by misunderstanding.

How to deal with rockets?

With our view of things, it is necessary to study the original technical documentation of rocket stoves carefully, but not at all because of inches-millimeters, liters-gallons and the subtleties of American technical jargon. Although they also mean a lot.

Note: a textbook example is “Naked conductor runs under the carriage.” Literary translation - a naked conductor runs under the carriage. And in the original Petroleum Engineer article, this meant “Bare wire runs under the crane trolley.”

The rocket stove was invented by members of survival societies– people with a unique way of thinking, even by American standards. In addition, they were not bound by any standards and norms, but, like all Americans, they automatically always converted everything into money, taking into account their own benefit; a person with a different worldview simply will not get along in America. And instinctive self-interest inevitably gives rise to egocentrism. He by no means excludes good deeds, but not out of spiritual impulse, but with the expectation of dividends. Not in this life, so in that one.

Note: How much the average citizen of the greatest empire in history is afraid of everything can only be understood by talking to them long enough. And sociopsychologists go out of their way to convince you that living in fear is normal and even cool. The rationale is clear: intimidated biomass is easily predictable and manageable.

Without heating and cooking, of course, you cannot survive. What is a stove for? For the time being, survivors were content with camp stoves. But then, according to the Americans themselves, in 1985-86. they were greatly impressed by two films that were released with a short interval and triumphantly went around all the screens of the world: the Soviet science fiction parody of the entire human race “Kin-dza-dza” and the Hollywood “The Day After”, about the global nuclear war.

The survivors realized that after the nuclear winter there would be no extreme romance, but there would be the planet Plyuk in the Kin-dza-dza galaxy. The newly-minted plukans will have to be content with “ka-tse” in small quantities, bad, expensive and difficult to obtain. Yes, in case anyone hasn’t watched “Kin-dza-dza” - ka-tse in Plyukan style, a match, a measure of wealth, prestige and power. It was necessary to come up with your own furnace; none of the existing ones are designed for post-nuclear blast.

Americans are very often endowed with a sharp mind, but a deep mind is found as a rare exception. A completely normal US citizen with an IQ above average may sincerely not understand how it is that someone else does not get what he himself has already “caught up with” and how someone else may not like what suits him.

If an American has already understood the essence of the idea, then he brings the product to its possible perfection - what if a buyer is found, you can’t sell raw iron. But technical documentation, which looks beautiful and neat, can be drawn up extremely carelessly, or even deliberately distorted. What's wrong with this, this is my know-how. Maybe I'll sell it to someone. Either there will be a trick or not, but for now know-how costs money. In America, such an attitude to business is considered quite honest and worthy, but there, a clinical alcoholic at work as a stopper would never miss a job and wouldn’t take a couple of bolts home for the farm. That, in general, is what all of America stands for.

And Russian breadth of soul is also a double-edged sword. Our master most often just from the sketch immediately understands how this thing works, but in the little things he turns out to be careless and overly trusting of the source code: how is it for a fellow craftsman to deceive his own man. If something isn’t there, well, it’s not necessary. It seems clear how everything is spinning there - my hands are already itching. And then, perhaps, until it comes to the hammer, chisel and accompanying literature, still count and count. Moreover, important points can be omitted, veiled or deliberately incorrect.

Note: An American acquaintance once asked the author of this article - how did we, really stupid ones, choose the very smart Reagan as president? And you, who are really smart, tolerate a slobbering senile with dyed eyebrows in the Kremlin? True, then in America no one in a bad dream would have dreamed that in the next century a black citizen with a Muslim name would be installed in the Oval Office, and his first lady would dig up a vegetable garden near the White House and begin to grow turnips there. Times is changing, as Bob Dylan once sang for a completely different reason...

Sources of misunderstandings

There is such a thing in technology - the square-cube law. Simply, when the size of something changes, its surface area changes by the square, and its volume changes by the cube. Most often this means changing the overall dimensions of the product according to the principle of geometric similarity, i.e. You can't just keep the proportions. In relation to solid fuel stoves, the square-cube law is doubly valid, because the fuel also obeys it: it releases heat from the surface, and its reserve is contained in the volume.

Note: a consequence of the square-cube law - any specific furnace design has a certain permissible range of its size and power, within which the specified parameters are ensured.

Why, for example, can’t it be made the size of a refrigerator and with a power somewhere around 50-60 kilowatts? Because a potbelly stove, in order for it to provide any heat, must itself be heated inside to at least 400-450 degrees. And in order to warm up the volume of the refrigerator to such a temperature at a given heat transfer, you need as much firewood or coal as will not fit in it. A mini-potbelly stove will also be of no use: the heat will escape through the outer surface of the stove, which has grown relative to its volume, and the fuel will not release more of it than it can.

The square-cube law applies threefold to the rocket stove, because she is “polished” in an American professional way. With our kondachka it is better to stay away from her. For example, here in Fig. an American development, which, judging by its demand, many of our craftsmen take as a prototype.

The fact that the exact type of fire clay is not indicated here will be something that our people will figure out later. But, to be honest, who noticed that, judging by the absence of an external chimney and the presence of transportation holes (carrying pipe), this stove is mobile with an open firebox? And most importantly, the fact that her drum used a 20-gallon barrel with a diameter of 17 inches (431 mm with change)?

Judging by the designs from the RuNet - no one at all. They take this thing and adjust it according to the principle of geometric similarity to a domestic 200-liter barrel with a diameter of 590 mm on the outside. Many people think of setting up a ash pit, but the bunker is left open. The exact proportions of vermiculite and perlite for lining the riser and molding the furnace body (core) are not specified? We make the lining homogeneous, although from what follows it will be clear that it should consist of an insulating and accumulating part. As a result, the stove roars, it eats only dry fuel, and a lot of it, and before the end of the season it becomes covered in smoke inside.

How was the rocket stove born?

So, without science fiction and futurology, the survivors needed stove for heating a home, operating with high efficiency on low-quality random wood fuel: wet wood chips, twigs, bark. Which, in addition, will need to be reloaded without stopping the furnace. And it most likely won’t be possible to dry it in a woodshed. Heat transfer after heating is needed for at least 6 hours to get enough sleep; getting burned in your sleep on Plyuk is no better than in America. Additional terms: the design of the furnace should not contain complex metal products, non-metallic materials and components that require production equipment for manufacturing, and the furnace itself should be accessible for construction by an unskilled worker without the use of power tools and complex technologies. Of course, no supercharging, electronics or other energy dependencies.

They immediately took a bed from the kana, but what about the fuel? For a bell-type furnace, it requires high quality. Long-burning stoves even operate on sawdust, but only dry ones, and do not allow stopping with additional loading. They were still taken as a basis, it was very attractive high efficiency, achieved in simple ways. But in attempts to make “long stoves” work on bad fuel, another circumstance became clear.

What is wood gas?

High efficiency is achieved largely due to the afterburning of pyrolysis gases. Pyrolysis is the thermal decomposition of solid fuel into volatile combustible substances. As it turned out (and the survivors have their own research centers with highly qualified specialists), the pyrolysis of wood fuel, especially wet wood, continues for quite a long time in the gas phase, i.e. The pyrolysis gases that have just been released from the wood still require quite a lot of heat to form a mixture that can burn out completely. This mixture was called wood gas.

Note: in RuNet, woodgas has created further confusion, because... in American vernacular gas can mean any fuel, cf. eg gas station - gas station, gas station. When translating primary sources without knowing American technical knowledge, it turned out that woodgas is simply wood fuel.

Before that, no one had seen wood gas: in conventional stoves it is formed immediately in the firebox, due to the excess energy of flaming combustion. The designers of long-burning furnaces came to the conclusion that the primary air needs to be heated, and the exhaust gases must be retained in a significant volume over a large mass of fuel, simply by trial and error, so they also overlooked wood gas.

This was not the case when burning bundles of twigs: here the draft immediately pulled the primary pyrolysis gases into the chimney. Wood gas could have formed in it at some distance from the firebox, but by that time the primary mixture had cooled, pyrolysis stopped, and heavy radicals from the gas settled on the walls of the chimney as soot. Which quickly tightened the channel completely; Hobbyists who build rocket stoves at random are familiar with this phenomenon. But the survival researchers eventually realized what was going on, and still made the necessary stove.

Who are you, the Rocket Stove?

There is an unspoken rule in technology: if it seems that it is impossible to create a device according to the given requirements, then, smart guy, read your school textbooks. That is, go back to basics. In this case, to the basics of thermodynamics. Survivors do not suffer from sick pride; they turned to the basics. And they found main principle operation of its furnace, which has no analogues in others: slow adiabatic afterburning of pyrolysis gases in a low flow. In long-burning furnaces, afterburning is equilibrium isothermal, requiring a large buffer volume subject to the square-cube law and an energy reserve in it. In pyrolysis gases in the afterburner expand almost adiabatically, but almost into the free volume. And now we are learning to think like an American.

How does a rocket stove work?

A diagram of the final fruit of the survivors' labors is shown on the left side of Fig. Fuel is loaded vertically into the bunker (Fuel Magazine) and burns, gradually settling down. Air enters the combustion zone through the ash pan (Air Intake). The blower should provide excess air so that it is enough for afterburning. But not excessively, so that the cold air does not cool the primary mixture. At vertical loading fuel and the blank lid of the bunker, the regulator, however, is not very effective, is the flame itself: when it gets too hot, it pushes out the air.

Then things begin to become non-trivial. We need to heat up a large oven with good efficiency. The square-cube law does not allow it: the meager heat will immediately dissipate so much that pyrolysis will not reach the end, and the thermal gradient from the inside to the outside will not be enough to transfer heat into the room; everything will whistle down the pipe. This law is harmful, you can’t break it in the forehead. Okay, let's look at the basics to see if there is anything there that is beyond his control.

Well, yes, there is. The same adiabatic process, i.e. thermodynamic without heat exchange with environment. There is no heat exchange - the squares rest, and the cubes can be reduced either to a thimble or to a skyscraper.

Let's imagine a volume of gas completely isolated from everything else. Let's say energy is released in it. Then the temperature and pressure will begin to increase until the energy release stops and freeze at a new level. Great, we have completely burned the fuel, hot flue gases can be released into a heat exchanger or heat accumulator. But how to do this without technical difficulties? And most importantly, how to supply air for afterburning without violating the adiabatics?

And we will make the adiabatic process nonequilibrium. How? Let the primary gases immediately from the combustion source go into a pipe covered with high-quality insulation with a low intrinsic heat capacity (Insulation). Let’s call this pipe a fire tube or a combustion tunnel (Burn Tunnel), but we won’t sign it (know-how! If you don’t catch up, give us money for drawings and consultations! Without theory, of course. Who sells fixed capital at retail.) On the diagram, so that not accused of “opacity”, let’s denote it with flame.

Along the length of the flame tube, the adiabatic index changes (this is a nonequilibrium process): the temperature first drops slightly (wood gas is formed), then increases sharply, and the gas burns out. You can release it into a storage tank, but we forgot - what will the gases be drawn through the flame tube? Supercharging means energy dependence, and there will not be an exact adiabatic, but something mixed with an isobar, i.e. efficiency will drop.

Then we will lengthen the pipe by half, maintaining the insulation so that the heat does not go away in vain. We bend the “idle” half up, making the insulation on it weaker; We’ll think about how to preserve the heat seeping through it a little later. In a vertical pipe there will be a temperature difference in height, and, therefore, draft. And a good one: the thrust force depends on the temperature difference, and with an average temperature in the flame tube of about 1000 degrees, it is not difficult to achieve a difference of 100 at a height of about 1 m. So, while we have made a small, economical stove-stove, now we need to think about how to use its heat.

Yes, it doesn’t hurt to further encrypt it. If we call the vertical part of the flame tube a primary or internal chimney, then they will guess the main idea, but we are not the smartest in the world. Well... let's call the primary chimney the most common technical term for vertical pipes with rising current - a riser. Purely American: correct and unclear.

Now let's remember about heat transfer after heating. Those. we need a cheap, always available and very capacious heat accumulator. There is nothing to invent here; adobe (Thermal Mass) was invented by the primitives. But it is not fire-resistant, it does not hold more than 250 degrees, and at the mouth of the riser we have about 900.

It is not difficult to convert high-potential heat into medium-potential heat without losses: you need to give the gas the opportunity to expand in an isolated volume. But, if you leave the expansion adiabatic, then the volume needed is too large. This means it is material and labor intensive.

I had to go back to basics again: immediately after leaving the riser, let the gases expand at constant pressure, isobarically. This requires heat removal to the outside, about 5-10% of the thermal power, but it will not be lost and will even be useful for quickly warming up the room during the morning fire. And further along the flow of gases – cooling is isochoric (in a constant volume); Thus, almost all the heat will go into the battery.

How to do this technically? Let's cover the riser with a thin-walled iron drum (Steel Drum), which will also prevent heat loss from the riser. The “drum” turns out to be a little high (the riser sticks out a lot), but it doesn’t matter: we will coat it 2/3 of the height with the same adobe. We attach a stove bench with an airtight chimney (Airtight Duct), an external chimney (Exhaust Vent), and the stove is almost ready.

Note: The riser and the drum covering it look like a stove hood above an elongated heil. But the thermodynamics here, as we see, are completely different. It is useless to try to improve a bell-type stove by building on it - only extra material and work will go away, and the stove will not get any better.

It remains to solve the problem of cleaning the channel in the bed. To do this, the Chinese have to break down the kan from time to time and wall it up again, but we are not in the 1st century. BC We live when kan was invented. We will install a secondary ash pit (Secondary Airtight Ash Pit) with a sealed cleaning door immediately after the drum. Due to the sharp expansion and cooling of the flue gases in it, everything in them that has not burned out immediately condenses and settles. This ensures the cleanliness of the external chimney for years.

Note: Secondary cleaning will have to be opened once or twice a year, so you don’t have to bother with the hinge-latches. Let's just make a lid from a metal sheet with screws and a mineral cardboard gasket.

Small rocket

The next task of the designers was to create a small continuous combustion stove on the same principle for cooking food in the warm season. IN heating season The drum cover (Optional Cooking Surface) of a large oven is suitable for cooking; it heats up to about 400 degrees. The small rocket stove had to be portable, but it was permissible to make it with an open firebox, because When it’s warm, you can cook outdoors or under a canopy.

Here the designers took revenge on the square-cube law by making it work for themselves: they combined the fuel bunker with the blower, see Fig. at the beginning of the section on the right. This cannot be done in a large furnace; precise adjustment of the furnace mode as the fuel settles (see below) will be impossible.

Here, the volume of incoming primary air (Primary Air) turns out to be small relative to the area of heat release and the air can no longer cool the primary mixture until pyrolysis stops. Its supply is regulated by a slot in the hopper lid (Cover Lid). The hopper, inclined at 45 degrees, optimizes the automatic adjustment of oven power for standard culinary procedures, but it is more difficult to make.

Secondary air for afterburning wood gas in a small stove enters through additional holes in the mouth of the riser or simply leaks under the burner if a cooking vessel is placed on it. If the small stove is close to the maximum size (about 450 mm in diameter), then for complete afterburning you may need an Optional Secondary Woodgas Frame).

Note: It is impossible to supply secondary air to the mouth of the riser of a large furnace through holes in the drum (which would increase the efficiency of the furnace). Although the pressure in the entire gas and smoke path is lower than atmospheric, as it should be in a furnace, due to strong turbulence, flue gases will be emitted into the room. This is where their kinetic energy, which is harmful to the furnace, comes into play; This is perhaps the only thing that a rocket stove has in common with a jet engine.

The small rocket stove revolutionized the class of camping stoves, especially camping stoves. A wood chip stove (Bond stove in the West) will help you cook a stew or wait out a snowstorm in a one- or two-person tent, but it won’t save a group caught in a spring hike by belated bad weather. A small rocket stove is only slightly larger; it can be quickly made out of nothing, but is capable of developing power up to 7-8 kW. However, we’ll talk about rocket stoves made from just about anything later.

Also, the small rocket stove gave rise to many improvements. For example, Gabriel Apostol provided it with a separate blower and a wide bunker. The result was a stove suitable for constructing a compact and fairly powerful water heater, see the video below. The large rocket oven was also modified, we will talk about this a little at the end, but for now we will focus on more significant things.

Video: water heater based on a rocket stove designed by Gabriel Apostol

How to sink a rocket?

A rocket stove with long-burning stoves has general property:you only need to run them on warm pipe. For a small one this is unimportant, but a large one on a cold chimney will only burn fuel in vain. Therefore, before loading standard fuel into the bunker after a long break in the firebox and kindling, a large rocket stove needs to be accelerated - fired with paper, straw, dry shavings, etc., they are placed in an open ash pit. The end of acceleration is judged by a change in the tone of the furnace hum or its subsidence. Then you can load fuel into the bunker, and it will ignite automatically from the booster fuel.

The rocket stove, unfortunately, is not one of the stoves that is completely self-adjusting to fuel quality and external conditions. At the beginning of combustion of standard fuel, the ash door or hopper lid in a small furnace is opened completely. When the stove begins to hum loudly, cover it “to the point of a whisper.” Further, during the combustion process, it is necessary to gradually cover the access of air, guided by the sound of the stove. Suddenly the air damper slammed shut for 3-5 minutes - no big deal, if you open it, the stove will light up again.

Why such difficulties? As the fuel burns, the flow of air into the combustion zone increases. When there is too much air, the furnace explodes, but do not rejoice: now the excess air cools the primary gas mixture, and the sound intensifies because the stable vortex in the riser is knocked into a chaotic lump. Pyrolysis in the gas phase is interrupted, no wood gases are formed, the furnace consumes too much fuel, and a deposit of soot cemented with bituminous particles settles in the riser. This, firstly, is a fire hazard, but most likely it won’t lead to a fire; the riser channel will quickly become completely overgrown with carbon deposits. How to clean it if you have a non-removable drum cover?

In a large furnace, a spontaneous change of mode occurs abruptly, when the top of the sticks drops to the bottom edge of the hopper, and in a small furnace - gradually, as the fuel mass settles. Because when cooking on the stove experienced housewife does not leave it for a long time, the designers considered it possible, for the sake of compactness, to combine a bunker with a blower in it.

This trick will not work with a large stove: the high riser pulls very hard, and the air gap needs to be so thin (and it also needs to be adjusted) that it is impossible to achieve a stable stove mode. It’s easier with a separate blower: it’s easier for the air to flow around the sides of a mass of fuel that is round in cross-section, and a flame that gets too hot pushes it there. The stove turns out to be self-regulating to some extent; however, within very small limits, so you still have to manipulate the blower door from time to time.

Note: It is impossible to make a bunker for a large oven for the sake of simplicity without a tight lid, as is often done. Due to the unregulated additional air flow through the fuel mass, it is unlikely to be possible to achieve stable operation of the furnace.

Materials, sizes and proportions, lining

Now let's see what a homemade rocket stove should look like from the materials available to us. Here, too, we need to be careful: not everything that is at hand in America is what we have, and vice versa.

From what?

For a large stove with a stove bench, more or less reliable experimental data is available for products with a drum from a 55-gallon drum with a diameter of 24 inches. 55 gallons is 208-odd liters, and 24 inches is almost exactly 607 mm, so our 200-liter is quite suitable without additional conversion. While maintaining the oven parameters, the diameter of the drum can be halved, to 300 mm, which makes it possible to make it from 400-450 mm tin buckets or a household gas cylinder.

The ash pit, bunker, firebox and riser will use pipes of different sizes, see below, round or profile. This way it will be possible to make an insulating lining of the firebox from a mixture of equal parts of oven clay and crushed fireclay, without resorting to brickwork; We’ll talk about the riser lining in more detail below. Combustion in a rocket furnace is weak, therefore the thermochemistry of gases is gentle and the thickness of the steel of all metal parts, except for the gas pipeline in the stove bench, is from 2 mm; the latter can be made from a thin-walled metal corrugated sheet, here the flue gases are already completely exhausted both in terms of chemistry and temperature.

For external coating, the best heat accumulator is adobe. If the dimensions indicated below are observed, the heat transfer of a rocket stove in adobe after combustion can reach 12 hours or more. The remaining parts (doors, covers) are made of galvanized metal, aluminum, etc., with sealing gaskets made of mineral cardboard. Conventional stove fittings are not suitable, it is difficult to ensure their tightness, and a cracked rocket stove will not work properly.

Note: It is advisable to equip the rocket stove with a view in the external chimney. Although the gas vent in the high riser seals the overall smoke path tightly, strong winds outside can suck the heat out of the bench prematurely.

Dimensions and proportions

The basic calculated values to which the rest are tied are the drum diameter D and its internal cross-sectional area S. Everything else, based on the size of the available iron, is determined as follows:

Drum height H – 1.5-2D.
Drum coating height – 2/3H; For the sake of design, the edge of the coating can be made oblique and curved, then 2/3H should be maintained on average.
The thickness of the drum coating is 1/3D.
Riser cross-sectional area – 4.5-6.5% of S; It's better to stay within 5-6% of S.
The height of the riser is the larger the better, but the gap between its edge and the drum tire must be at least 70 mm; its minimum value is determined by the viscosity of the flue gases.
The length of the flame tube is equal to the height of the riser.
The cross-sectional area of the flame tube (fire duct) is equal to that of the riser. It is better to make the fire duct from a square corrugated pipe, so the furnace mode will be more stable.
The cross-sectional area of the blower is 0.5 of its firebox and riser. A more stable furnace mode and its smooth adjustment will be provided by a rectangular corrugated pipe with sides 2:1, laid flat.
The volume of the secondary ash pan is from 5% of the original volume of the drum (excluding the volume of the riser) for a stove from a barrel to 10% of the same for a stove from a cylinder. Interpolation for intermediate drum sizes is linear.
The cross-sectional area of the external chimney is 1.5-2s, where s is the cross-sectional area of the riser.
The thickness of the adobe cushion under the external chimney is 50-70 mm; if the channel is round, it is counted from its lowest point. If the bed is on wooden floors, the pillow under the chimney can be halved.
The height of the bench coating above the external chimney is from 0.25D for a 600 mm drum to 0.5D for a 300 mm drum. You can do less, but then the heat transfer after heating will be shorter.
External height chimney– from 4 m.
The permissible length of the gas duct in the bed - see next. section

The maximum thermal power of a rocket stove made from a barrel is approximately 25 kW, and a stove made from a gas cylinder is about 15 kW. The power can be adjusted only by the size of the fuel load. By supplying air, the oven is put into operation, and nothing more!

Note: in the original survivalist stoves, the riser cross-section was taken at 10-15% S based on very wet fuel. Then, there, in America, rocket stoves with a bench for bungalows appeared, designed for air-dry fuel and more economical. In them, the riser cross-section is reduced to the recommended ones and here it is 5-6% S.

Riser lining

The efficiency of a rocket stove largely depends on the thermal insulation of the riser. But American lining materials, alas, are not available to us. In terms of reserves of high-quality refractories, the United States has no equal; there they are considered strategic raw materials and are sold even to trusted allies with caution.

From our available materials for heating engineering, they can be replaced with light fireclay bricks of the ShL brand and ordinary self-excavated river sand with a large admixture of alumina, correctly laid, see below. However, these materials are porous; in the oven they will quickly become saturated with carbon deposits. Then the oven will roar with any air supply, with all that follows. Therefore, we need to surround the riser lining with a metal shell, and the end of the lining must be covered with oven clay.

Lining diagrams for 3 types of furnaces are shown in Fig. The point here is that as the size of the drum decreases, the share of its direct heat transfer through the bottom and unlined part increases according to the square-cube law. Therefore, while maintaining the desired thermal gradient in the riser, the lining power can be reduced. This makes it possible to correspondingly increase the relative cross-section of the annular lowering of the flue gases in the drum.

For what? Firstly, the requirements for the external chimney are reduced, because The external rod now pulls better. And since it pulls better, then the permissible length of the hog in the bed drops more slowly than the size of the stove. As a result, if a stove from a barrel heats a stove bench with a length of up to 6 m, then a stove made from a cylinder half as long is 4 m.

How to line with sand?

If the riser lining is fireclay, then the residual cavities are simply filled with construction sand. There is no need to carefully prepare a river self-dug for lining entirely from sand; just select large debris. But they pour it in layers, in 5-7 layers. Each layer is compacted and sprayed until a crust forms. Then the entire backfill is dried for a week, the top edge is covered with clay, as already mentioned, and the construction of the furnace continues.

Balloon rocket

From the above, it is clear that it is more profitable to make a rocket stove: less work, fewer unsightly parts in sight, and the stove warms up almost the same. Thermal curtain or a warm floor in the Siberian frost will heat a room of 50 square meters with a power of 10-12 kW. m or more, so here, too, a balloon rocket turns out to be more profitable; a large barrel will rarely have to be launched at full power with maximum efficiency.

The craftsmen apparently understood this too; at least some. For example, here in Fig. – drawings of a balloon furnace-rocket. On the right is the original; the author seems to have wisely understood the initial developments and, in general, everything turned out right for him. On the left are the necessary improvements taking into account the use of air-dry fuel and heating the bed.

A fruitful idea is a separate supply of heated secondary air. The furnace will be more economical and the fire tube can be made shorter. The cross-sectional area of its air duct is about 10% of the riser cross-section. The oven always operates with the secondary completely open. First, the mode is set by the primary valve; Precisely adjust with the hopper lid. At the end of the firebox, the stove will roar, but here it’s not so scary; to clean the riser, the author of the design provides a removable drum cover. It, of course, must have a seal.

Rockets made from anything

Canning

Tourists, hunters and fishermen (many of them members of survival societies) soon adapted the small rocket stove into a camp stove made from empty tins. It was possible to reduce the influence of the square-cube to a minimum by using horizontal fuel supply, see the diagram on the right. True, at the cost of some inconvenience: the sticks need to be pushed inward as they burn out. But the furnace mode began to hold fast. How? Due to the automatic redistribution of air flows through the plenum and over/through the fuel. The power of a can rocket stove lies in the range of 0.5-5 kW depending on the size of the stove and is regulated by approximately three times the amount of fuel loading. The basic proportions are also simple:

The diameter of the combustion chamber (combustion chamber) is 60-120 mm.
The height of the combustion chamber is 3-5 times its diameter.
The cross-section of the blower is 0.5 from its own combustion chamber.
The thickness of the thermal insulation layer is not less than the diameter of the combustion chamber.

These proportions are very approximate: changing them by half does not prevent the stove from working, and efficiency on a hike is not so important. If the insulation is made of wetted sandy loam, as described above, the joints of the parts can simply be coated with clay (left position in the figure below). Then, after 1-2 fires, the stove will acquire strength that allows it to be transported without special precautions. But in general, any of the available non-combustible materials will do the insulation, trace. two pos. A burner of any design must provide free air flow, 3rd position. A rocket stove welded from a steel sheet (right position) with sand insulation is twice as light and economical as a potbelly stove of the same power.

Brick

We won’t talk about large stationary rocket furnaces: all the original thermodynamics are in tatters in them, and they are deprived of one of the main advantages of the original furnace - ease of construction. We'll tell you a little about rocket stoves made from brick, clay or stone fragments, which can be made in 5-20 minutes when you don't have tins at hand.

Here, for example (see the video below), is a thermodynamically complete rocket oven made of 16 bricks laid dry. The voice acting is in English, but everything is clear even without words. A similar one can be built from fragments of brick (see figure), cobblestones, or sculpted from clay. A stove made from rich earth is enough for one time. The efficiency of all of them is not so great, the height of the combustion chamber is too small, but it is enough for pilaf or to quickly warm up.

Video: rocket oven made of 16 bricks (eng)

New material

Among the domestic developments, the Shirokov-Khramtsov rocket stove deserves attention (see figure on the right). The authors, not caring about survival in the splash, used a modern material - heat-resistant concrete, adjusting all the thermodynamics to it. The components of reinforced concrete are not cheap; a concrete mixer is needed for mixing. But its thermal conductivity is much lower than that of most other refractories. The new rocket stove began to work more stable, and it became possible to release some of the heat outside in the form of infrared radiation through heat-resistant glass. The result was a rocket stove - a fireplace.

Do rockets fly in a bathhouse?

Wouldn't a rocket stove be suitable for a sauna? It seems that you can build a heater on the drum cover. Or a flow one instead of a bed.

Unfortunately, the rocket stove is not suitable for a sauna. To get light steam, you must immediately warm up the walls with thermal (IR) radiation, and immediately, or a little later, the air, by convection. To do this, the oven must be a compact source of infrared and a convection center. Convection from a rocket furnace is distributed, and it provides little IR at all; the very principle of its design excludes significant losses due to radiation.

In conclusion: to the rocket makers

Successful designs of rocket stoves still rely more on intuition than on precise calculations. Therefore, good luck to you too! – the rocket stove is a fertile field for craftsmen with a creative streak.

Drawings and videos of a rocket stove required for DIY installation

Do-it-yourself jet stove: diagram, drawings, step-by-step instructions for making a rocket stove, etc. + video

The jet stove or rocket stove appeared as a result of a deviation from the traditions of manufacturing equipment for heating a room. It is considered an economical heat generator, the design of which is elementary. Therefore, many people are thinking about building a jet furnace with their own hands.

Description, advantages and disadvantages of the rocket stove

A heat generator for heating indoor air is called a rocket stove or jet stove, since when it operates in case of excessive air supply it makes special sounds. This noise can be mistaken for the roar of a jet engine. In normal mode, the equipment operates with a barely audible rustling sound.

A rocket stove serves as a device for heating a home and cooking food. It takes about 6 hours to burn one batch of firewood in such equipment, more than in a standard metal stove. The reason for this is the creation of a heat generator based on a top-burning furnace.

The flame from the jet furnace may burst out

The advantages of the rocket stove include:

independence from fuel energy;
simplicity of design, consisting of accessible parts, connected in a matter of minutes;
the ability to provide a lot of heat, despite the quality of the loaded fuel.

The jet furnace also has some disadvantages:

manual control, which implies constant monitoring of equipment operation;
danger of burns, because the walls of the equipment become extremely hot;
It is inappropriate to use in a bathhouse, since it cannot be warmed up.

Species

A unit that emits a rocket-like hum during operation can be:

portable (a unit made of metal pipes, buckets or a gas cylinder); Portable rocket stoves are mass-produced by industry
stationary (made from fireclay bricks and metal containers); Such a unit is more difficult to build than a metal furnace
equipment for heating air with a stove bench. The stove bench is equipped behind the back wall of the stove

Portable structures are manufactured in large quantities, because they are used for hiking. The basis of these heat generators is a pipe made up of several sections.

True, such structures, unlike units based on fireclay bricks, are not reliable. Walls made of refractory blocks increase the heat transfer of the jet furnace.

If desired, you can add a bench in the form of a sofa or bed, decorated with clay or sawdust.

Parts and operation of a jet heat generator

A basic rocket furnace is a device consisting of two pipe fragments connected by a bend at an angle of 90 degrees.

The combustion chamber in this heat generator is usually a zone in the horizontal part of the structure.

But sometimes fuel is placed in the vertical section of the apparatus, for which a rocket stove is constructed from two pipes of different lengths, mounted vertically and connected by a common horizontal channel.

Primary and secondary air passes through the furnace

The operation of a jet stove is based on two actions: the unhindered passage of wood gases through the pipe and the afterburning of gases produced during fuel combustion.

Wood chips and firewood are placed in the firebox of this heat generator after a highly flammable material such as paper ignites. A container with water or other contents is placed on the open section of the pipe.

At the same time, between the structure and installed capacity leave a small space necessary to create traction.

The processes occurring inside a stationary reactive furnace resemble the operation of pyrolysis heating units

Calculation of parameters (tables)

The volume of the furnace should be determined wisely, because it is it that affects the power and amount of heat generated by the heating equipment.

Calculating the dimensions of a jet heating equipment, use the indicator of the internal diameter of the drum D, the value of which can vary between 300–600 mm. You also need to know the cross-sectional area of the drum.

To determine this indicator of the rocket stove, you should use the formula: S = 3.14 * D2 /4.

The main dimensions of the jet furnace are presented in the table:

Particular importance is attached to the length of the flue with the stove bench. The maximum permissible values are shown in the table:

The volume of the secondary ash chamber is also an important indicator, depending on the volume of the drum and the primary chimney.

Construction raw materials for the construction of a non-standard furnace

The production of jet heating equipment will require:

barrels with a volume of 200 liters and a diameter of 0.6 meters, an empty cylinder from under liquefied gas or tin buckets to build a furnace drum;
square or round steel pipes 2–3 mm thick, which are needed to create a blower, combustion chamber and primary chimney;
fireclay crushed stone and oven clay as thermal insulation materials;
adobe, which serves as the outer coating layer;
fireclay bricks;
sand from the bottom of the river;
pieces of sheets of zinc-coated steel or aluminum for the manufacture of lids and doors;
asbestos or basalt cardboard, which serves as a sealant.

The tools you will need to build a rocket furnace are: welding machine. And if you plan to make heating equipment from bricks, then you will have to take:

trowel;
mortar spatula;
hammer-pick;
jointing;
sharp-angled sledgehammer;
level;
plumb line;
roulette

Preparation for assembling heating equipment

When choosing a location for a rocket stove, follow some rules:

jet heating equipment is placed only in a room with an area of at least 16 m²;
Without floorboards under the stove, installation of equipment will be easier;
It is prohibited to place wooden beams above a structure that produces heat;
if it is intended that the chimney will go through ceilings, then the heating equipment is placed in the middle of the house;
the heat generator cannot be installed near the external contour of the house, otherwise the room will lose heated air;
The jet device must not be placed next to walls and partitions of wooden materials.

To make it convenient to add fuel to jet heating equipment, it is wiser to place it facing the entrance. It is important to leave at least a meter of unoccupied area around the rocket stove.

IN small house builders advise setting aside a place for the stove in the corner. In this case, the firebox should be directed in one direction, and the bed (if it is made) – in the other.

The stove stands on a special platform that protects the floor from high temperatures

Having found suitable site for the rocket stove, they begin to prepare it for construction work. If boards are laid on the floor in the house, then in the place where the equipment will be installed, they will need to be removed. A hole is dug under the exposed floor, the bottom of which is necessarily pressed.

Before construction work, a special solution should be mixed. It consists of sand and clay combined in a 1:1 ratio. You will need enough water so that the construction raw materials have the consistency of sour cream, that is, ¼ of the amount of dry ingredients.

Step-by-step instructions for making it yourself

If you plan to make a rocket stove from a gas cylinder, then you don’t have to be afraid of difficulties. The steps to create equipment from such construction raw materials are quite simple:

from a cylinder with a volume of 50 liters is cut off top part to build a kind of cap;
The balloon is cut off at the top and bottom
Based on the instructions in the drawing, all parts of the product are welded to each other, that is gas cylinder, a pipe with a diameter of 10 cm (future chimney), a pipe with a diameter of 7 cm (internal channel) and another pipe with a diameter of 15 cm (firebox);
Dimensions in mm
the space between the two pipes is filled with a material that retains heat, for example, sand, which has been thoroughly calcined, that is, cleared of organic substances;
To give the structure stability, the legs are welded.

To build a rocket stove with a stove bench, which involves the use of bricks, you need to proceed differently:

The area for arranging the firebox is deepened by removing 10 cm of soil. The combustion chamber is formed from fireclay bricks. Formwork is created along the contour of the structure being manufactured. To make the base strong, it is recommended to lay reinforcement mesh or metal rods in it;
The platform will harden in about two days
The structure is filled with liquid concrete. Then they wait for the solution to harden and finish the work. The bricks are laid in a continuous line, creating a platform for the stove. After this, the walls of the structure are formed, placing several rows of brick blocks;
The lower channel of the structure is constructed, with one line of bricks laid across to block the combustion chamber. The blocks are placed, leaving the vertical channel and the firebox opening open;
Two sectors of the furnace at this stage of construction should be open
Find the body from the old boiler and cut off the top and bottom covers on it. A flange is installed at the bottom of the resulting pipe through which a horizontal heat exchanger will pass. The parts must be connected to each other with a continuous weld;
The work requires accuracy
An outlet pipe is inserted into the barrel, after which they take a metal brush and scrape off the rust from the walls of the container. The cleaned barrel is treated with a primer, and a little later with paint that is resistant to high temperatures;
The horizontal chimney is connected by welding to the side outlet - the future ash pit. To facilitate its cleaning, a sealed flange is installed;
The fire tube is laid out from refractory bricks. At the same time, a channel 18 cm high and wide is formed inside the structure. When doing this, they constantly use a building level, which allows you to control the verticality of the product;
The height of the pipe is determined in advance
The flame tube is covered with a protective casing, and the resulting gaps are sealed with perlite. The lower area of the vertical channel is sealed with raw clay, the function of which is to prevent the thermal insulation material from spilling onto the floor;
From the boiler, on which the top and bottom have been cut off, a fuel tank is formed. A handle must be welded to it;
To improve the appearance, the structure is treated with adobe putty, consisting of sawdust and raw clay. The first component of the composition serves in the same way as crushed stone in concrete, that is, it prevents cracking of the furnace walls. It is recommended to apply adobe putty over perlite backfill;
They create the facade of the stove, for which the stove contour is laid out from stone, bricks, adobe and sand. The back side of the structure is filled with crushed stone, and the front side with adobe mixture, making the surface perfectly flat;
A casing made of metal barrel. The lower pipe of the container is directed towards the bed. The bottom of the structure is treated with raw clay, which will ensure its tightness;
A channel made of corrugated pipe is connected to the combustion chamber. It will serve as a link between the firebox and the outside atmosphere;
At this stage the oven looks almost finished
A test firing of the stove is carried out, watching how the gases are removed from the horizontal chimney. After this, the heat exchanger pipes are connected to the lower pipe installed on a red brick platform;
The stove is equipped with a smoke exhaust pipe. The junction of the chimney and the heat generator is sealed with fire-resistant coating and asbestos cord;
Using clay and adobe, the bed is given the desired shape. Only the horizontal section of the structure is left unsealed, which will then be used during cooking.
The oven functions as a whole system

Design improvement

A bench with a gas duct inside is not the only option for upgrading a rocket stove. The design can be improved with a water jacket connected to the heating system in which water circulates. It is advisable to give this part of the structure the appearance of a coil created from a copper pipe twisting onto the chimney.

This design provides even more heat

Another way to improve a jet furnace is to organize the flow of heated secondary air into the flame tube. This will increase the efficiency of the heat generator, but will lead to the deposition of a large amount of soot in the primary chimney. Therefore, it is better to make sure that the drum cover can be removed if necessary.

Subtleties of operating an unconventional stove

A rocket furnace is heated in a similar way to a top combustion heat generator. It turns out that the kindling of equipment called a rocket must be carried out according to certain rules:

the main raw material for heating the unit must be added only after the structure has been well heated, for which purpose sawdust or paper is first placed in the blower sector and set on fire;
they must react to the muting of the hum emanating from the stove - they put a large batch of fuel into the combustion chamber, which will ignite on its own from the hot remains of sawdust;
the process is closely monitored, that is, after laying the firewood, the damper is fully opened, and after some time, when the equipment makes a hum, it is closed to produce a sound similar to a rustling;
as necessary, the damper is closed more and more, otherwise the firebox will be filled with an excess volume of air, which will disrupt the pyrolysis inside the fire tube and lead to the creation of a strong hum.

Since the jet stove was originally created for use in the field, its design is extremely simple. This allows the production of the unit to be carried out by ordinary home handyman. But, despite its apparent lightness, the rocket stove must be assembled, taking into account the correct ratio of parameters. Otherwise, the equipment will be unproductive.

Ksenia Zubkova
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Source: //legkovmeste.ru/stroitelstvo-i-remont/otoplenie/reaktivnaya-pech-svoimi-rukami.html

DIY rocket oven - instructions!

Unfortunately, in our country almost no one knows about the rocket stove. Meanwhile, such a design is extremely useful in a number of cases due to the almost complete absence of soot during operation and the high combustion temperature.

Jet stove

Rocket stove

Today we'll talk about how to make a rocket oven with your own hands.

Operating principle

Hot gases, instead of a chimney, enter a special hood, where they burn out (hence the absence of soot). At the same time, the temperature increases even more, and the pressure, on the contrary, decreases. The cycle is constantly repeated and soon the furnace reaches the combustion mode with maximum draft (the strength of the latter depends on design features and quality of installation).

Rocket stove

The temperature in the bell can reach 1200ᵒC, as a result of which all waste burns almost without residue, and the exhaust consists mainly of carbon dioxide and water vapor.

Pay attention! Thanks to this, the chimney can be laid under the floor or through some kind of heating structure (a couch, for example, or a bench). What's more, the hot hood can be used to heat water, cook food, dry fruits, etc.

Jet furnaces

The advantages include:

high efficiency;
no soot;
high temperature;
the possibility of using cones, damp branches, dry plant stems as fuel - almost everything burns at a temperature of 1200ᵒ;
low fuel consumption - approximately four times lower than in a standard design.

Types of rocket stoves

There are several types of rocket (or jet, as they are also called) stoves.

Portable structures made from tin containers (paint cans, buckets, etc.). Excellent helpers on a construction site or on a hike, which can be made in just a few hours.
Furnaces made of refractory bricks and metal barrels, intended for heating heat-intensive masses. They are distinguished by a horizontal chimney installed underground and an external riser to provide draft.
Completely brick structures are used for air-heated floors. They consist of several chimney pipes at once.

Pay attention! Due to the complexity of implementing the third option, only the first two will be considered in this article.

Making a reaction furnace from a brick and a metal barrel

In this case, the work traditionally begins with preparing everything necessary.

Making a reaction furnace from a brick and a metal barrel, drawing

Stage 1. Materials and equipment

For construction you will need:

fireclay brick;
steel barrel 200 l;
chimney pipe;
metal brush;
old barbecue;
fire resistant paint;
bayonet shovel;
expanded clay;
fittings;
adobe;
perlite;
cement mortar;
trowel. Making a jet furnace from a brick and a metal barrel

Stage 2. Preparation

Step 1. A pit is dug in the floor (if possible) approximately 30-50 cm deep. This is necessary so that the level of the horizontal chimney does not rise too much.

Step 2. The steel barrel will serve as a hood for the furnace. First, the barrel is fired and cleaned of soot with a wire brush, after which it is painted with fire-resistant paint.

Pay attention! Paint is applied only after the chimney outlet flange has been installed.

Stage 3. Foundation

Step 1. Preparing the formwork for the future foundation.

Step 2. In the place where the firebox will be, several bricks are driven into the ground.

Step 3. Steel reinforcement is laid at the bottom.

Step 4. Bricks are laid level around the bottom point of the combustion chamber.

Step 5. The base is filled with concrete mortar.

Making a reaction furnace from a brick and a metal barrel

Stage 4. Masonry

After the solution has dried, you can begin laying the rocket stove.

Pay attention! To do this, you need to use only refractory clay.

Step 1. On the first tier, the masonry rises up, leaving only a hole for the combustion chamber.

Step 2. At the second level, the lower channel of the furnace is formed.

Making a reaction furnace from a brick and a metal barrel

Step 3. On the third, the channel is covered with masonry so that there are two holes - for the combustion chamber and the vertical channel.

Pay attention! The bricks do not need to be hewn after laying - they will still have to be hidden with adobe and expanded clay.

Step 4. Preparation for laying the vertical channel. In addition to the barrel itself, this will require an old water heater of approximately 150 liters.

A flange is built into the barrel to connect the chimney. It is also advisable to install a tee here for cleaning the chimney.

Step 5. The ascending part of the structure is placed using the “boot” method. The internal cross-section of this part should be approximately 18 cm.

Step 6. A piece of water heater is placed on the ascending part, and the voids between the walls are filled with perlite. The upper part of the perlite is sealed with fireclay clay.

Step 7. The base of the furnace is lined with bags filled with sand, the base of the casing is coated with clay. The voids between the bags and the body are filled with expanded clay, after which the base is finished with the same clay.

Step 8. The chimney is connected, an inverted steel barrel is placed on the ascending part.

Step 9. A test run of the furnace is carried out, after which the barrel is painted with fire-resistant paint.

Making a reaction furnace from a brick and a metal barrel, diagram

Stage 5. Chimney lining

Step 1. The chimney is lined with sandbags and filled with expanded clay.

Step 2. The structure is given the appropriate shape using fireclay clay.

Pay attention! The rocket stove requires a large amount of oxygen during operation, so it is recommended to install an air duct from the street.

All that remains is to install the old barbecue in the neck of the firebox and close it with a lid. The seams are sealed with clay. That's it, the brick rocket oven is ready for use.

A stove-bed built on the principle of a rocket stove

Stove-bed, built on the principle of a rocket stove, diagram

Stove-bed, built on the principle of a rocket stove, foundation

Stove-bed, built on the principle of a rocket stove, masonry

Making a camping and garden stove

In this design, as in the one described above, the operating principle is to isolate the fire and direct the thermal energy to the right place.

Stage 1. Preparing everything you need

To prepare a portable rocket stove you will need:

two tin containers of different diameters;
a couple of corners;
steel clamps ø10 cm;
stainless steel pipe for chimney;
fine crushed stone;
Bulgarian;
metal scissors. Making a camping garden stove Making a camping garden stove Making a camping garden stove In the second bucket - the lower part of the rocket stove, we cut a hole for the pipe. We cut the metal into petals and bend it inside the bucket. for dishes From wire we bend the burner for dishes We heat the rocket stove

Stage 2. Assembling the structure

Step 1. A lid for the structure is made from a smaller bucket. To do this, a hole is made in it for the chimney (the cover is not removed). In this case, it is better to bend the “petals” inward - this way the pipe will be fixed more securely.

The lower half of the bucket is cut off with a grinder.

Step 2. A hole is cut in the bottom of another container to connect the firebox. The tin is cut into “petals” with scissors and bent inward.

Step 3. The forward flow is assembled from a pipe and a couple of corners. The pipe is then inserted into the bucket and connected there to the “petals” using a steel clamp. That's it, the forward flow of the rocket furnace is ready.

Step 4. The space between the direct flow and the walls of the bucket is filled with fine crushed stone. The latter will perform two functions in the design at once - thermal insulation and thermal accumulation.

Step 5. The second bucket (lid) is placed on the jet stove.

Step 6. A hotplate is bent from steel wire.

Pay attention! Instead of a burner, you can install three bricks.

Step 7. All that remains is to paint the structure with heat-resistant paint (preferably gray or black). For melting, the direct flow outlet pipe will be used.

Mini jet oven

Mini jet stove, kindling

Operating rules for rocket stoves

Rocket stoves, as well as other long-burning designs, need to be launched onto a warm pipe. And if for the second version of the stove this is not so important, then for the first, a cold chimney will only lead to wasted burning of fuel. For this reason, the structure needs to be preheated - heated with sawdust, paper, etc.

It is also worth noting that the jet stove is unable to self-adjust, so at first the vent opens completely, and closes only after the structure begins to hum strongly. Subsequently, the availability of oxygen gradually decreases.

About the rocket stove in the bathhouse

Jet wood stove with deck chair

Many people are probably interested in the question: is it possible to use a jet stove in a bathhouse? It would seem that it is possible, because it is quite easy to equip a heater on a tire.

In reality, such a design is not suitable for a bathhouse. For light steam, you first need to warm up the walls, and only then, after some time, the air. For the latter, the oven must be a center of convection and thermal radiation (IR). This is the problem - in a rocket furnace, convection is clearly distributed, and the design does not provide for losses due to thermal radiation at all.

DIY rocket oven

Conclusions

Be that as it may, today in the manufacture of rocket stoves there is more intuition than real accurate calculations, therefore, this is an almost limitless field for creativity.

We also suggest that you familiarize yourself with the video instructions for making a rocket stove.

– Do-it-yourself jet stove

Source: //svoimi-rykami.ru/stroitelstvo-doma/pechi_i_mangaly/pech-raketa-svoimi-rukami.html

DIY long-burning brick rocket stove: drawing, instructions, photo

A rocket stove made of long-burning bricks, despite its simplicity of design, can solve a number of problems for owners of dachas and private houses. These include not only heating and cooking functions, but also the creation original interior and comfort in the room.

Operating principle

During the thermal decomposition of solid organic fuel, gaseous substances are released, which also decompose and turn into wood gas during combustion, which has a high level of heat transfer during combustion.

In conventional solid fuel stoves, wood gas goes into the pipe along with the gas, where it cools and settles on the walls in the form of soot. In a rocket-type furnace, due to the horizontal channel, gases move more slowly, do not have time to cool, but burn out, giving off a large amount of heat.

In models of jet heating devices of complex design, heated air and gas pass through a number of internal channels. Then they move to the upper part of the body, under hob, where it burns completely. For such a rocket there is no need for additional boost. The draft in them is created by the chimney, and the longer its length, the more intense the upward flow.

Operating principle

This diagram shows the operating principle of a rocket stove with a stove bench

Advantages and Disadvantages

Long combustion rocket stoves have the following advantages:

high efficiency - at least 85%;
high speed of heating the room - 50 m² will become warm in less than 1 hour;
absence of soot - the exhaust during fuel combustion does not form soot, but is formed in the form of steam and carbon;
the ability to operate on solid fuel of any type;
low consumption - the fuel consumption of a rocket stove is 4 - 5 times less than that of a conventional stove under equal conditions: combustion time and heating temperature;
the possibility of installing a warm bed;
Duration of heat retention in a well-heated structure without adding fuel - up to 12 hours.

This stove has many advantages, but there are also disadvantages

The disadvantages include:

manual method of controlling a heating device - fuel burns out quickly and requires regular reporting;
the high heating temperature of some structural elements threatens owners with burns in case of accidental contact;
the heating speed does not allow the use of a rocket stove for baths;
the aesthetic component of such a device is not for everyone and is not suitable for every interior;
danger of carbon monoxide entering living rooms.

Materials

Do-it-yourself building materials for the construction of a long-burning rocket stove are selected depending on the calorific value of the fuel. For laying the main part of the body, a simple red one is usually used kiln brick. The firebox and combustion bunker are lined with fireclay bricks.

If you plan to use high-calorie fuel (for example, coal), then refractory bricks are used for the construction of almost all parts of the structure. Fasten masonry elements aqueous solution mixtures of sand and clay.

Regardless of the type of design for a long-burning rocket stove, you will need to buy stove accessories:

blower;
grates;
firebox doors;
intermediate cap;
chimney pipe.

Tools

To build a rocket-type furnace with your own hands, you need to prepare in advance a set of tools for work, which should consist of:

trowels for scooping and distributing the solution. It is more convenient to work with a tool with the handle moved slightly to the side;
picks or hammers - picks for trimming individual parts of brick;
grinders with a diamond blade for sawing whole blocks into quarters and halves;
mallets with a rubber tip for leveling bricks in masonry;
twisted cord - moorings;
building level;
square and tape measure;
shovels.

You also need to stock up on two containers for preparing the solution, concrete and a metal mesh for sifting the ingredients.

How to do it yourself?

Before you make a rocket stove, you need to decide on the location of its installation, the dimensions of the future design, and develop a diagram. The masonry technology itself is quite simple; any novice builder can master it.

The simplest design of a rocket furnace can be built from 20 bricks per summer cottage and use it to heat food brought from home.

Selecting a location

Before starting construction, the first thing is to choose a location. It is recommended to place rocket-type brick stoves closer to the front door. In this case, after cleaning, the ash will not need to be carried across the entire room, which will have a positive effect on the overall dustiness of the room.

It is also desirable that at the place where the pipe exits there are no rafters located closer to the chimney than 40 cm. And yet, the stove should not be adjacent to external wall at home, so that expensive heat does not go to heating the street.

Preparation of the solution

Cement mortar will quickly crack under the influence of high temperatures, so for laying heating devices made of bricks, only a mortar consisting of clay and sand is used.

Their proportions are determined experimentally, depending on the quality of the clay. Most often in a ratio of 1:2 or 1:3, and the higher the fat content of the clay, the less it is added to the solution.

First, the clay must be soaked, strained, and then sand must be added. The resulting solution should have a consistency similar to thick sour cream. You can check its viscosity level in the following way:

place a wooden stick or trowel handle into the mixture;
remove the tool and shake well;
check the thickness of the adhering layer: if less than 2 mm add clay, more than 3 mm add sand.

The preparation of the mortar must be approached with all responsibility, since only a plastic mixture of the required thickness can fill all the unevenness of the bricks and ensure their strong adhesion.

Laying a rocket furnace of 20 bricks

Ordering a rocket stove for 20 bricks

Example of a brick rocket stove

Laying a rocket stove with a stove bench

A brick rocket stove, even equipped with a stove bench, has small sizes. The order shown in the figures (below) allows you to assemble the structure without the use of metal products. Only the doors will be made of iron. Subsequently, the body can be coated with clay to give it a more rounded shape.

Row No.	Number of bricks, pcs.	Description of the masonry	Drawing
1	62	Forming the base of the furnace	(click to enlarge)
2	44	Formation of the base of channels for heating the bed along the entire structure. Fastening mortgages for mounting a cast iron door
3	44	Repeating the outline of the second row
4	59	Complete channel blocking. Beginning of the formation of a vertical smoke channel and firebox
5	60	Construction of a bed	(click to enlarge)
6	17	Continuation of the laying of the smoke channel
7	18
8	14
9; 10	14	Formation of a smoke channel	(click to enlarge)
11	13
12	11	Beginning of laying the chimney pipe. This is where the channel begins, through which the air from the hob will fall down to move to the stove bench
13	10	Completion of the formation of the surface for the hob. Laying an asbestos pad, which is covered with sheet steel.	(click to enlarge)
14; 15	5	Closing the chimney channel and forming a low wall between the stove bench and the hob.

After completion masonry work The homemade rocket stove must be dried, carefully, heating at low intensity. First, no more than 20% of the required amount of firewood is placed in the firebox, and the device is heated twice a day for 30 - 40 minutes.

According to this scheme, the stove is heated until it outer surface will not remove damp stains. Depending on the size of the device, drying may take from three to eight days. During this time, the room should be well ventilated, especially in summer.

Accelerating drying can lead to cracking of the masonry, that is, the device will become unsuitable for further heating.

Finished look

You need to launch a brick rocket stove only when the chimney is warm. For a small device, this property is not so significant, and a larger oven is cold pipe It's just a waste of wood.

Therefore, to bake a rocket before loading the fuel quota after a long break in operation, you need to heat it with paper, dry shavings, straw, etc., placing them in a ash pit with the door open. When the hum in the stove decreases in pitch or subsides, then you can load all the fuel into the firebox; it should ignite by itself from the existing fire.

A rocket stove with a stove bench is not a completely self-regulating device for external conditions and fuel energy efficiency. Therefore, at the beginning of the fire with the normal amount of fuel, the ash door is left in the open position. After the stove begins to hum strongly, it is covered until the sound emitted is barely audible.

Only dry wood can be used to heat the stove; wet wood will not allow the stove to warm up to the required temperature, which can lead to reverse draft.

Conclusion

The brick jet stove is becoming an increasingly popular heating device for small buildings, both temporary and permanent residence. This is explained by the simplicity of execution, low cost of material, long battery life and high heat transfer of this design.

The rocket stove is one of the types cooking ovens running on wood fuel. Stationary stove models are also used for heating.

She got her name from the hum that is heard at the beginning of the heating. When the combustion mode is correct, it subsides. The shape of the structure also resembles a rocket - vertical cylinder. The furnace is also called a reaction furnace.

A similar principle was used in Korea and China for heating houses in winter. Travelers in earlier times noted that significantly less firewood was wasted than in a traditional Russian village.

Jet furnaces, product drawings

Rocket stoves are divided into portable and stationary. The first devices are smaller in size and have a simpler design. She reminds inverted letter "G". Fuel is placed in the lower crossbar. Thanks to the vertical shape of the main part, there is natural craving.

Photo 1. Drawing and finished version of a metal rocket stove with dimensions, left and top view.

As the temperature rises, the device works more and more efficiently. Its power is enough to quickly heat water for cooking. for several people. To prevent the wood from burning out too quickly, you need to regulate the draft in the stove. To do this, close or close the fuel door completely.

Portable jet stoves mass-produced. Most popular models "Robinson" and "Ognivo". Due to the simplicity of the design, you can make them yourself.

Stationary devices are somewhat more complicated. The air ducts in the hood are made in such a way that the heated air first rises. Transferring heat to the inner walls, it gradually falls down. Then it passes into the chimney located at the bottom.

Photo 2. Drawing of a rocket stove made of brick and a metal barrel. The arrows show the parts of the device.

This stove is quite economical to use, since it burns not only wood, but also pyrolysis gases. The chimney duct of the stove is sometimes not taken out of the room immediately, but is carried out inside a stove bench made of brick and/or clay. This bed warms the room to a comfortable temperature. The structure itself is made from large diameter pipes, barrels or bricks.

Important! The device needs in preheating before combustion. First, paper, newspaper or something else that ignites quickly is ignited. And only the firewood is placed in the warmed-up firebox.

Long-burning rocket stove made of brick

Since brick accumulates heat, such devices are well suited for heating rooms. Taking into account the duration of combustion, one fill of fuel is enough for 6-8 hours maintaining a comfortable temperature.

Sometimes the oven is made entirely of brick. The only fittings (doors) you will need are steel or cast iron. In other cases, the outer part of the stove hood is made from a barrel or wide pipe.

Attention! Brick oven requires a separate foundation, not related to the one being built for the building itself. It is advisable to plan its location before construction begins.

A device made of a pipe with a water circuit, diagram

The furnace structure is welded from iron pipes of different diameters.

If you plan to heat a small room, the stove hood can be made from waste gas cylinder.

In a larger house, it would be suitable for these purposes. iron barrel.

If you install a water circuit on the stove chimney, you can get a long-burning boiler that will heat the room well.

The water circuit is usually made from gas cylinders.

"Robinson"

This is a simple and reliable camp stove. She's quite capable quickly (in 10 minutes) boil a liter water. In this case, there is no need to add firewood.

The design was developed back in the last century, but due to its advantages it is still used today. "Robinson" is mass-produced, but It is not difficult to assemble it yourself.

"Flint"

This oven is similar to the previous version. But the combustion chamber in it shorter and at a more obtuse angle in relation to the chimney. This stove is shaped like an inverted letter “G”.

How to make a rocket stove with your own hands

He has several stages— selection of a suitable design; selection of materials and tools; direct production.

Project selection

When choosing a suitable project, consider the following factors:

The purpose of the stove is whether it requires only cooking food or also heating the room.
Available materials.
Approximate power. It depends on how many servings of food or how much room the device will be enough for.

Materials

For a brick structure you will need:

fireclay (fireproof) brick;
fireproof mixture for masonry;
concrete mortar (for the base);
mineral wool;
asbestos;
a whole barrel or an empty gas cylinder for the cap (optional);
stove doors - combustion chamber and ash pan;
if the cap is brick - a thick sheet of stainless steel according to the size of its cross-section.

For finishing the stove the following are used:

fireproof paint;
clay;
stones;
etc.

For metal, take:

Round metal pipe with diameter about 150 mm and length no more than 90 mm(better about 60 mm).
Profiled (rectangular) pipe with a cross-section of 100—120 mm and length about a third round.
Instead of a rectangular pipe, you can take a sheet of steel thick 3 mm.
3 nuts.
Steel rods, plates or long bolts for legs.

Reference. For better traction take a profiled pipe with the side no more than the diameter of a round one.

Preparing tools

For production you will need:

trowel;
level;
welding machine;
bayonet shovel;
metal brush;
level;
Bulgarian.

Manufacturing, device sizes

There are many variations on this theme. Let's consider making two in principle different types jet stove. This is a brick stove with a stove bench, which is used indoors, and a camp stove, assembled from metal. If necessary, changes are made, combinations of methods are possible (for example, a heating and cooking device, but made of pipes covered with clay or stones).

How to make a brick oven with a stove bench

First stage— foundation arrangement. A rectangular recess is dug under it, which is then filled with concrete.

For strength, it is better to pre-install the reinforcement. The base must be strictly horizontal.

After the concrete solution has hardened Brick laying begins. External walls are located along the perimeter of the concrete platform. A combustion chamber is formed. On one side of it there is a combustion chamber with a hole for loading firewood. On the other side there are air ducts.

Important! Each row of bricks is also checked with a level. This is done in both planes - horizontal and vertical.

In the combustion chamber also leave a hole for cleaning ash which is closed by a door. When this chamber is ready, a metal barrel is put on it. The gaps are filled with insulation, for example, mineral wool.

If the barrel is not used, it is installed on top cooking stove. Asbestos insulation is placed under it.

The chimney is connected to the air duct and discharged to the street.

Then finished the device is decorated. For example, it is coated with clay and covered with paint. Another option is to leave the brickwork.

Jet stove for camping

It consists of two compartments, connected to each other. To assemble it, first cut the pipes at an angle 45°. If instead of the second pipe they took metal sheet, cut it into the following parts:

two with sides 300 mm and 150 mm;
two - 300 mm and 100 mm;
and one 150 and 100 mm.

Photo 3. Ready-made jet stove for hiking. The device is made of metal pipes.

Then weld them together. You will also need another plate to separate the fuel compartment, its dimensions are 200 mm and 100 mm.

All fragments are welded together in accordance with the diagram. The round pipe is attached to the bottom of the rectangular pipe and in the middle relative to the sides.

Welded from scraps of reinforcement grate. It is convenient to make it retractable in order to lay firewood and then slide it inside the firebox.

The pipe is sawed off 4 rings. They are attached to the top so that the dishes do not block the draft hole.

In a collapsible version legs are installed. Nuts are welded from below, into which long bolts are then screwed. There is another way. Rods or scraps of steel sheet are welded to the bottom. It is less convenient to transport, but there is no need for assembly.

When the design is ready, it needs to be painted. Only fireproof paint is used. This will protect against corrosion and also cover solder marks.

Possible difficulties

When laying bricks, it is not easy to accurately calculate the size of the holes for the firebox and ash doors. That's why you can lay out a row with a door without mortar, “dry”, and figure out how best to position it. And then lay out the bricks, fastening them with mortar.

When making a stove from pipes, it is difficult to calculate the location of their connection. Therefore, first, a round fragment is sawed off and placed on the rectangular one in the right place. Around draw a line with a marker, along which the cut is made. If the fuel part is assembled from separate plates, It will be more convenient to cut the hole before welding them among themselves.

Useful video

Watch a video that demonstrates the process of lighting a camping rocket stove and describes the characteristics of the device.

Pros of using a rocket stove

Jet furnaces Quite economical to use. But for super-efficient operation it is important that the fuel is dry, otherwise secondary combustion of gases will not occur.

Rocket stove not suitable for installation in a bathhouse. The fact is that for the desired effect it is necessary that the walls of the room first heat up. And in the mode created by this furnace, it is the air that is heated.

As a heating device in a permanent residence, such a device is not always convenient.

The simple and cheap design of the rocket stove began its march around the world from North America, where it is still very popular in rural areas. It is known on all continents, including distant Australia. The heating unit captivates amateur enthusiasts with its simplicity and energy efficiency, which, combined with its low cost, makes it extremely attractive for manufacturing at home. Of course, with a jet furnace big house not to heat, but in a country house or in a small garden house it would be more than appropriate. Surprisingly, but true - only a few people know about this amazing design. And this is in a country where cold weather lasts longer than six months! Today we will fill this gap and tell you everything we know about the warm and cozy “rocket”, including the smallest details of how to make it yourself and the intricacies of its operation.

Jet stove - what is it?

The home heat that comes from a jet stove cannot be provided by any modern heater.

A jet stove, or, as it is also called, a rocket stove, actually has nothing in common with modern technologies. The only thing that makes this heating unit look like a space vehicle is the intense flow of flame and the humming associated with improper operation. Nevertheless, it cannot be said that the rocket stove is a completely backward device in technical terms. Despite its simple design, it uses the most advanced methods of burning solid fuels:

pyrolytic combustion of gases released during dry distillation of solid fuel;
movement of gaseous products through the furnace channels, which does not require forced ejection due to draft.

This is what a simple jet-powered stove looks like

The simplest “rocket” is a curved piece of large diameter pipe. Firewood or other fuel is placed in a short horizontal section and set on fire. At first, the heating device works like an ordinary potbelly stove, but this is only until the temperature of the longer vertical part, which acts as a chimney, rises. The red-hot metal promotes the re-ignition of flammable substances and the appearance of a vacuum at the top point of the chimney. Due to increased draft, the air flow to the firewood increases, which significantly increases the burning intensity. In order to achieve even greater efficiency from this original device, the firebox opening is equipped with a door. When the cross-section of the air channel decreases, the supply of oxygen to the firewood stops and its pyrolytic decomposition into gaseous hydrocarbons begins. But in such a simple installation they will not burn completely - for this you will need to set up a separate area for afterburning the flue gases. By the way, it is this, as well as the thermal insulation of the chimney, that allows more complex “missiles” to successfully compete with other solid fuel units. As for the simplest design we are considering, it is often used for cooking or heating food. All that is required for this is to equip a convenient platform for a pot or kettle on the vertical section of the stove.

Geography of application of rocket heating units

Being a simple and convenient heating and cooking unit, the rocket stove is widely used in both mobile and stationary versions. Most often it is used:

for heating residential premises;
as equipment for drying fruits;
for heating greenhouses;
to ensure normal conditions work in workshops or garages;
to maintain above-zero temperatures in warehouses, utility rooms, etc.

Thanks to its simplicity, unpretentiousness and reliability, the jet heater enjoys well-deserved respect among fishermen and hunters, car rally enthusiasts and survivalists. There is even a special version, the purpose of which is indicated by the name - “Robinson”.

Advantages and disadvantages of the rocket stove

Despite its simple design, the rocket stove has many advantages:

efficiency level at the level of the best examples of modern heating equipment operating on solid fuel;
efficiency - to achieve the required temperature, the reactive unit will consume four times less firewood than a traditional oven design;
heating temperature above 1000 °C;
the ability to use solid fuel of any type, including dry plant waste, cones, pine needles and shavings;
complete combustion and environmental friendliness - during operation, the flame temperature increases so much that the soot ignites. Rocket stove smoke consists primarily of water vapor and carbon dioxide;
possibility of additional fuel loading for continuous operation heating device;
simplicity and reliability;
the presence of portable structures intended for mobile use.

The heating unit is not without its drawbacks. Operation of the device is associated with the risk of carbon monoxide entering the home. The stove cannot be used to heat a large house, and attempts to install a water heat exchanger in the combustion zone lead to a decrease in thermal power and disruption of normal operation. The disadvantages include the low aesthetic value of the design, which, however, is a very ambiguous statement, since for lovers of ethno-style the design of the stove is a real find.

Types of jet heating devices. Choosing a design for self-production

Craftsmen have developed several designs of rocket stoves suitable for mobile or stationary use:

portable units made of metal pipes, cans or buckets;
jet heating devices from a gas cylinder;
ovens built from fireclay bricks and metal containers;
heating heat generators with a stove bench.

The most difficult to manufacture are the structures, the construction of which requires the skills of a mason. However, if you have detailed diagrams of serial layouts, even a novice home craftsman can handle this work.

Portable rocket stove

Portable rocket stoves are mass-produced by industry

Hiking options are represented by the simplest designs, which are based on the same pipe bent or welded from individual sections. The improvements affected only the installation of a partition for arranging the ash pit, in which a slot is made for air leakage. Often, the lower part of the loading chamber is equipped with a grate to supply air directly to the combustion zone. The opening for storing firewood is equipped with a door, which subsequently regulates the air supply.

The requirements for a mobile design also extend to convenience during cooking, so the upper section of the chimney must be equipped with a stand for metal utensils.

Gas cylinder unit

The use of a gas cylinder is the next step in the development of jet heating devices. More complex design allows you to significantly increase the thermal power and efficiency of the furnace. All that is required to manufacture the installation is a household gas cylinder or fuel barrel, sections of thick-walled steel pipes and a metal sheet 3–5 mm thick.

A rocket stove made from a gas cylinder can be used to heat small utility rooms

If you have a piece of steel pipe with thick walls and a diameter of more than 30 cm, a rocket stove can be made from it. This option will allow you to avoid labor-intensive operations associated with disassembling the factory gas tank.

How such a design works can be seen in the diagram below. Firewood loaded into the firebox burns due to the flow of air through the loading window. Afterburning of combustible gases occurs in a pipe installed inside the cylinder due to the supply of secondary air. To enhance the effect, the inner chamber is insulated, which makes it possible to raise the temperature inside above 1000 °C. Hot gases hit the bell as they move and enter the outer chamber, the walls of which act as a heat exchanger. Having given up their energy, the combustion products are discharged through a chimney cut into the lower part on the back side of the cylinder.

To create the draft necessary for stable operation of the rocket stove, the top of the chimney is raised at least 4 m relative to the loading window.

Combined rocket stove made of brick and metal barrel

The use of fireclay bricks for arranging the firebox and internal chambers of a jet heating device transforms the “rocket” into the category of stationary structures. The high heat capacity of the materials used allows heat to be accumulated and released within several hours, which is why such units are often installed in residential premises.

Furnace structure with refractory lining of the working area

Jet stove with stove bench

Like other solid fuel stoves, the "rocket" has the disadvantage that most of the heat is lost through the chimney. Despite this, certain advantages of its design make it easy to get rid of this disadvantage. The thing is that the unit was called reactive for a reason, but because of the high rate of excision of burning gases. This feature can be turned into a benefit by significantly increasing the length of the smoke exhaust channels.

Scheme of a jet stove with a stove bench

This idea found its implementation in massive stationary structures with a couch in the form of a sofa or bed. It is successfully made from brick or rubble stone, decorated with a plastic mass of clay and sawdust. Thanks to the high heat capacity of the materials used, the stove can retain heat all night, which, combined with high efficiency, makes the heating unit very attractive for installation in residential premises.

When choosing a design for manufacturing at home, you need to take into account the features of its operation. As a camping option, they choose a mobile unit - it will be enough to warm up, dry clothes and cook lunch. In order to occasionally heat small technical rooms, a portable structure made from a gas cylinder is used. If you need to heat a small country house or cottage, then best option than a jet heating unit with a stove bench simply does not exist.

We build a rocket oven with our own hands

Suggested for self-made The design is the elite of rocket heating devices. After construction, it will delight the owner for a long time with comfort and cozy warmth even in the most severe frost. As you might have guessed, we are talking about a unit with a stove bench. Despite the fact that such a design is the most complex, the diagrams, instructions and descriptions we presented will allow you to build a stove in just 2-3 days.

Device and principle of operation

A rocket furnace consists of several chambers and channels. The bunker for loading firewood is made of fireclay bricks and is equipped with an opening in the lower part for air supply. It has a refractory lining and a channel that connects the firebox with a vertical flue (fire pipe or riser). A metal barrel is used as the casing of the rocket furnace, inside of which the afterburning chamber is lined with magnesite or fireclay bricks. The heat exchanger of the heating unit is not only a steel container, but also long horizontal channels of the stove bench made of galvanized steel pipes or bricks.

The processes occurring inside a stationary reactive furnace resemble the operation of pyrolysis heating units

There is no need to use refractory materials to construct heat exchange channels. A well-burnt red brick is sufficient.

The body of the stove and trestle beds is formed from sandbags, stone or brick fragments and coated with a clay composition. Good heat storage capacity finishing materials allows the structure to release heat for several hours after the wood has completely burned out. To remove combustion products, a high chimney is used, which can pass both indoors and outdoors.

The high performance of the “rocket” is explained by the method of fuel combustion, which tends not so much to direct-flow heating units as to pyrolysis boilers. The operation of the furnace is accompanied by the active release of gas components, which are burned in the riser. The cap helps reduce the flow rate of hot gases, otherwise they simply would not have time to oxidize. By the way, heating the upper part of the flame tube creates a vacuum at its end, due to which active combustion of the fuel occurs. In this case, such a high temperature arises in the riser that even the soot ignites. Nevertheless, at the point of transition from the vertical channel to the horizontal heat exchanger, experts recommend installing an ash pan, equipping its chamber with a small door to allow periodic maintenance.

Calculation of basic parameters, drawing

There is no need to give the exact dimensions of a rocket stove with a stove bench - its dimensions and configuration completely depend on the characteristics of the room. The presented method for calculating parameters, based on the use of the proportions of all parts of the rocket furnace, will be quite sufficient to design a high-performance, efficient unit.

To perform the calculation, it is enough to know the diameter D and height H of the external heat exchange casing (drum).

The height of the flame tube is at least 1.3H.
The gap between the riser and the cap is 0.1–0.15H.
External clay coating is carried out no higher than 1/3H.
The thickness of the heat-accumulating layer should be no more than 1/3D.
The cross section of the flame tube is 0.25–0.3D.
The height of the ash pan is up to 10% of the vertical dimensions of the casing.
The cross-section of the blower should be 50% less area riser
The thickness of the adobe cushion above the heat exchanger is at least 1/4D.
The chimney height is more than 4 m.
The length of the horizontal heat exchanger is calculated based on the volume of the drum. If a standard fuel barrel is used, it can reach 6–8 m.

As you can see, it is not difficult to determine the dimensions of all elements of the furnace, especially since its design allows for some liberties in terms of dimensions and configuration.

For perfectionists and those who are afraid to experiment, we present a drawing of a heating unit, drawn to scale on a marked sheet of paper. If necessary, taking exact dimensions from it will not be difficult.

Drawing of a stationary jet heating system

Materials and tools

The construction of a jet furnace does not require any special equipment. The only power tools required during the work process are a welding machine and a grinder, and even then just for a few minutes - to separate the barrel lid and configure the heat exchanger pipes. Any owner can also find everything else:

trowel (trowel);
bushhammer;
building level and plumb line;
roulette;
container for preparing the solution;
bayonet shovel;
tamping;
buckets;
concrete trowel.

Although the design of the “rocket” is undemanding in terms of materials, you will still have to buy some of them. Here is a list of what will be needed during the construction process:

refractory bricks of any type;
metal barrel for making a casing;
a pipe Ø30–40 cm, which will hold the thermal insulation coating of the vertical channel. You can use the housing from an old water heater, a suitable capacity of an industrial receiver or a hydraulic accumulator;
galvanized steel pipes with a diameter of more than 25 cm, which will be needed as a heat exchanger;
a steel pipe for arranging a chimney with a diameter of 150 mm and an elbow for its outlet at 90°;
ash pan hatch;
blower door;
a special heat-resistant mixture for preparing the solution (can be replaced with sand and clay);
perlite for thermal insulation of the riser;
red brick;
rubble stone or brick waste;
sawdust or chaff.

Since the barrel will be only partially embedded in the oven, it will have to be painted to increase the aesthetic value of the unit. To do this, you will additionally need a metal brush, a solvent to degrease the metal surface, a primer and any heat-resistant paint.

Site selection and other preparatory activities

When determining the construction site, you should take into account the requirements that apply to all designs of solid fuel stoves with an open flame:

the area of the room in which it is planned to install a jet heating device with a sunbed must be at least 16 m2;
the absence of logs (floor beams) under the stove body will greatly simplify installation;
there should be no wooden rafters or ceilings above the fireplace;
if part of the chimney passes through the ceiling, then the stove is installed closer to the central part of the house. In this case, the pipe can be secured near the ridge;
You should not install a heating structure close to the outer contour of the building - precious heat will go outside. It is better to attach the unit to one of the internal walls;
It is not recommended to build a jet device near wooden walls and partitions. In this case, separate accommodation is chosen.

It is also important how convenient it will be to light the rocket stove and throw firewood into it. To do this, the firebox is placed towards the entrance, providing at least 1 m of free space in front of it.

One of the many options for installing a stove in the middle of the room

In a small room, it is convenient to place the rocket stove in the corner, with the loading hopper oriented in one direction and the lounger in the other.

Having chosen a place, they begin to prepare it for future construction. If the room has a wooden floor, then the part of it that will be under the stove is removed. After this, a shallow pit is dug, the bottom of which is compacted using a tamper.

In addition, it is necessary to prepare a metal barrel for installation. To do this, cut off its cover along the contour. In this case, part of the thickening in the form of a metal hoop is left to ensure the rigidity of the base of the casing. Most likely, the fuel container will be dirty and rusty, so it is better to clean it before installation.

The last thing to do before starting construction is to prepare the mortar. It is best to use a special heat-resistant composition, which can be purchased at construction stores, but you can get by with a simple mixture of sand and clay in a ratio of 1:1 or 1:2, depending on the fat content of the latter. Water will be needed up to ¼ of the volume of dry ingredients - the output should be a composition reminiscent of thick sour cream.

Instructions for the progress of work

As already mentioned, to make a rocket stove with a stove bench, it will take much more effort and time than when making a metal unit. It will help make the task easier and reduce time step by step instructions with illustrations of all stages of construction.

The place where the firebox will be formed is deepened by 10 cm and laid out with refractory bricks, after which formwork is installed along the contour of the stove. To strengthen the foundation, it is necessary to install reinforcement from building mesh, reinforcement Ø10–20 mm or scraps of metal pipes and corners.
Arrangement of formwork
Lay out the base of the working chamber according to the level.
The base of the loading chamber is lined with refractory bricks
The structure is poured with concrete. Further work can begin immediately after the solution has set. As a rule, one day is enough for this.
Pouring the foundation
The base of the jet furnace and the combustion chamber are formed from refractory bricks laid in a continuous pattern.
Rocket stove base
The masonry is raised in several rows side walls designs.
The walls are formed using fireclay bricks installed on the edge
The lower channel of the heat-generating rocket is being equipped.
The combustion chamber is covered with a row of bricks laid transversely in such a way as to leave two openings open - the firebox and the riser (vertical channel).
Method of covering the horizontal part of the working chamber
An old casing from a storage boiler is prepared for installation. To do this, the device is cut off on both sides to obtain a large-diameter pipe.
Furnace parts prepared for installation
The lower part of the fuel and lubricants container is equipped with a flange into which the horizontal heat exchanger pipe will fit. Welds must be continuous to ensure tightness and, accordingly, safety of the structure.
Installation of the lower pipe is carried out by welding
After the outlet pipe is cut into the barrel, it is cleaned of rust, coated with a primer and several layers of heat-resistant paint.
TO horizontal chimney a side outlet is welded, which acts as an ash pan. To clean it, the channel is equipped with a sealed flange.
A fire tube is made of fireclay bricks. The shape of its internal channel is a square with a side of 18 cm. During work, be sure to control the vertical position of the structure using a plumb line or a building level.
The height of the vertical channel depends on the size of the outer drum
A casing is installed on the flame tube, after which the gaps between the metal container and the walls of the vertical channel are filled with perlite. To avoid spillage of thermal insulation on the floor, the lower part of the riser is carefully sealed using a clay mixture.
Riser thermal insulation method
The firebox cap is made. You can use a cut-off part of the water heater as it, providing it with a comfortable handle.
The furnace body is formed using brick or stone masonry. For this purpose, you can also use sandbags placed at the base of the vertical channel.
The oven body can be lined with sandbags

The unassuming spring appearance is hidden with the help of adobe coating. To make it, up to 50% of large sawdust or chaff (chaff) is added to the clay solution.

Coating the furnace body

Additives in a clay mixture perform the same role as crushed stone in concrete. They are needed so that during drying and subsequent work with variable thermal loads, the surface of the furnace does not crack.
The perlite backfill on top also needs to be sealed with coating.
The front part of the oven is formed. For this purpose anyone in a suitable way(brick or masonry, sandbags, adobe) lay out the outline of the stove. The inner part is filled with crushed stone, and the upper part is given the desired shape using adobe mixture.
An outer casing made of a metal barrel is installed on the prepared base, orienting the container with the lower pipe towards the stove bench. The lower part of the container is sealed with clay.
Installation of a casing - a metal barrel
Using a corrugated pipe, a channel is led to the firebox, which connects the firebox to the external atmosphere. If it is not installed, the stove will consume warm air from the room, which will be replaced by cold masses coming from outside. On the side of the firebox, the channel will need to be closed as soon as the firewood is completely burned out. This will not allow air from the street to penetrate into the heat exchange channels.
Duct for supplying air from outside the building
To check the operation of the rocket stove, the first kindling is carried out, during which they make sure that the gases freely exit into the horizontal chimney.
Heat exchanger pipes are connected to the lower pipe, which are installed on a base formed of red brick.
The chimney is being installed. All connections of parts of horizontal and vertical channels are sealed using asbestos cord and fire-resistant coating.
Using the same method as in the manufacture of the stove body, give the required configuration to the stove bench.
Fully formed oven with bench
The barrel can be completely covered with adobe, leaving only the horizontal platform open, which is convenient to use for heating food.
The chimney brought outside is equipped with a condensate and tar trap, and the upper cut is protected from precipitation using a cap.
The outer part of the chimney is equipped with a liquid trap

Tests of the rocket furnace are carried out only after the adobe coating has completely dried. Otherwise, the decorative coating may crack.

View of the finished rocket stove with a stove bench

For safe operation of a rocket stove, the room must be equipped with carbon monoxide sensors.

Modernization of rocket heat generator

To expand the scope of application of reactive heating stoves, they are being modified, increasing the convenience and versatility of the design. In mobile structures, the platform intended for cooking is often replaced with a full-fledged stove. It is convenient to use such a hob in your own backyard for household purposes - for preparing food for pets or during the period of preserving food for the winter. A special feature of this type of rocket furnace is a wide and flat horizontal channel into which hot gases from the nozzle are directed. Passing under the surface of the stove, they heat it red-hot, after which they go into the vertical chimney. Comfortable legs give the structure stability, and the original shape allows you to use the unit as a stand or table when it is not in use for its intended purpose.

A jet stove with a stove is a necessary thing in a suburban area

A liquid heat exchanger cannot be installed in the flame tube of a jet furnace, but this does not mean that it cannot be used as a heat generator in a water heating system. To do this, the “rocket” is equipped with a kind of circuit of radiator plates, which create a kind of labyrinth in the afterburning zone. Thanks to their heating, heat is removed from the afterburning chamber to the water jacket. The efficiency of the unit depends on the area and heat capacity of the plates, so they are made in the form of massive metal strips with an area of up to ¾ of the cross-section of the fire channel. It must be said that such a heat exchanger is best used to produce hot water using the rocket stove itself in the traditional way.

Diagram of a rocket unit equipped with a water circuit

The rocket stove with a convector has an original design. To increase heat transfer, vertical tubes are mounted on the surface of the outer casing, performing the same role as the air channels of the buleryan. Cold air is trapped at the bottom of the tube heat exchangers and is heated as it moves upward. This ensures forced convection, which further increases the thermal efficiency of the installation.

Rocket heat generator casing equipped with a convector

Features of using reactive furnaces

Being a long-burning system, the rocket stove requires preheating before use. As a rule, in mobile installations no one complies with this requirement - they consume little fuel, and the potbelly stove itself is most often used according to the principle “it works, oh well.” In stationary structures, warming up the furnace before starting is extremely important, since with a cold flame tube there is no question of any afterburning. The firewood will burn without giving off heat, and the chimney will very quickly become covered with soot, tar and creosote.

The stove is heated using wood chips, paper or shavings, which are loaded into the firebox and set on fire. Reaching operating mode is judged by a humming sound in the heat channel. A loud sound indicates ineffective operation of the unit. As soon as the hum begins to subside, you need to start adding the main fuel. The vent should be completely open for the first 10–15 minutes. Then the air supply is reduced, focusing on the sound of the stove - it should “rustle” or “whisper”. After the wood burns out, the air duct of the firebox is covered to prevent heat from escaping from the room. Once every 2-3 days, ash is removed using a metal scoop and poker.

Maintenance of the jet stove is carried out no more than once a season. To do this, open the ash pan door, through which the remaining soot is removed. If necessary, clean the smoke channel using the hatch of its trap. It must be said that proper operation of a jet heater never leads to smoke in the room. All that is required of the owner is to follow the recommendations for using the “rocket” and not neglect safety rules.

DIY rocket stove: subtleties and nuances of construction (video)

Unique technical characteristics, almost zero cost and availability of materials for construction cover all the disadvantages of the jet furnace. If you wish, you can build a full-fledged heating device over the weekend, including arranging a comfortable couch. “Rocket” is also convenient because it does not require highly qualified stove maker, but external design allows the implementation of even the most unusual design concept.

This rocket stove is a convenient, compact, portable unit, which is not intended for heating a room, but for preparing food while camping or on vacation. You can easily and quickly heat up food, boil water, fry meat or fish. Making this structure with your own hands is not difficult. The design has many advantages over others.

Advantages of the Robinson rocket stove

First of all, it is worth noting that such a stove is convenient to maintain and light (you can use a wide variety of fuel: grass, dry branches, firewood, paper, hay), it is easy to assemble and disassemble. The device is simple and reliable. This design does not emit smoke and soot, so you will not need to spend a long time washing the dishes from dirt. If you decide to make the unit from heat-resistant material, then the walls will withstand temperature up to 800°. The original “Robinson” was very carefully developed by physicists, so at the moment these designs are popular all over the world.

Device

The Robinson portable stove is made on the basis of the principle: fuel burns in a bunker compartment, the fire enters the combustion zone and rises up the chimney. First, all the energy goes to heating the chimney; after it is heated, due to the high temperature, the gases burn out again.

"Robinson" is made from a pipe 100x150 millimeters. It is important that the cross-section of the chimney is the same size as that of the firebox, otherwise reverse draft may occur. Legs are typically made from threaded rod and screwed into place, however this option not the most convenient. As a support, you can use either stationary legs or a steel sheet that is welded to the bottom. IN original oven“Robinson” does not have a channel for air supply, a cover for combustion regulation too No. However, there are many homemade options where this drawback is eliminated. We will look at the most standard of them.

How to make “Robinson” with your own hands

So, we have a glass (sometimes called the heart of the oven). He has oblong shape. There is a suction at the bottom (air rises from it and enters the chamber). There are two hoppers on the sides of the glass. One bunker is welded under angle 90°(it is used for ignition) and has one chamber, the second - at an angle of 45°, it contains two chambers: a loading chamber and a chamber air leak. Next to the choke there is a box (we insert it tightly into the glass), into which the ash is collected after burning the fuel.

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