What is a rocket stove? Rocket stove: do-it-yourself rocket, drawings and video, long-burning rocket stove, for heating. DIY rocket stove. Drawings

The basis of the design is two vertical chambers of different sizes, connected at the bottom by a common channel. The smaller container is called the combustion chamber. It is used first for ignition, then for burning wood.

The stove is usually heated using flammable materials such as wood shavings, wood chips, paper, and small dry twigs. Using special dampers in the lower compartment of the combustion chamber, you can regulate the traction force.

After the entire system, including the chimney and large chamber, has warmed up, the rocket stove will begin to perform its functions of heating the room. You can determine this moment by how the hum that arose at the beginning subsides.

The room is heated by a smoke duct that runs through the room or along its perimeter. The combustion products, having passed along the entire length of the pipe and given off heat into the room, come out cold. That is, thermal energy is retained to the maximum inside the heated room.

Advantages and disadvantages

In order to fully understand the mechanism of operation of the rocket stove and begin its manufacture, it is worth studying all the pros and cons of such equipment.

Among the main advantages of a jet stove for heating a home, which made it so popular, the following are noted:

At the same time at work jet furnaces there are the following disadvantages:

• To fire the simplest device, only dry wood is used, since the presence of additional moisture can lead to improper operation of the unit and will cause reverse thrust; if you use fuel with excess moisture in a more complex design, the heating device will not warm up to the optimal temperature for the pyrolysis process;
• during operation of the jet unit there is a need to constantly be nearby, ensuring compliance with safety regulations;
• The power of the rocket stove is enough to maintain a comfortable room temperature, but it is not enough for a steam room, so it cannot be used in a bathhouse.

DIY masonry

Craftsmen and amateurs who are able to build such a rocket stove need to pay attention to the only difficulty that may arise on the way to the goal. We are talking about obtaining a building permit. As for the work itself, anyone can do it.

The peculiarity of the stove is that the unit has a curved combustion chamber: in the shape of the letter J or L. Thanks to this design, the fire moves in a horizontal direction, and the heat, reaching the bend of the pipe, rises under the influence of the turbulence effect. In turn, the resulting draft maintains the intensity of combustion.

Inside the large chamber there is a thermal riser through which heated gases rise upward and, having given off some of the heat, descend again through the channels. Secondary air release promotes almost complete burnout of ash and soot, which significantly increases the heat transfer of the furnace.

The most common material for creating a reaction stove with your own hands is clay. However, nowadays it is quite appropriate to use other materials, such as tiles or stone.

A brick rocket stove shows a high level of efficiency. Having passed all the way from the combustion chamber to the smoke channel, the gas coming out under the influence of high temperatures (from 900 to 1200 degrees) turns into water vapor and carbon dioxide. At such indicators, soot combustion occurs.

Almost all flammable substances are suitable for firing a rocket stove: recycled materials, cones, branches, sawdust, etc.

If you want a homemade rocket stove to instantly release heat into the room, you need to leave the cap free, without covering it with clay. If you need to retain heat from combustion longer, then this product should be insulated with brick or clay.

Order

First row laid out solid. The bars must lie in exact accordance with the pattern shown in the diagram: this will give the entire base strength. For masonry you will need 62 red bricks.
The image clearly shows the connection of the three sections of the furnace.
The corners on the side bars of the firebox façade are cut off or rounded: this way the structure will look neater.

Second row. At this stage of the work, internal smoke channels are laid through which gases heated in the firebox will pass, giving off heat to the bricks of the stove bench. The chimneys are connected to the firebox, which also begins to form in this row.

The first brick of the wall separating the two channels under the stove bench is cut diagonally. This “nook” will collect the remaining combustion products, and the cleaning door installed opposite the bevel will allow you to easily clean it.
To lay the level you will need 44 bricks.

On the second row, the doors of the blower and cleaning chambers are mounted, which are necessary for periodically tidying up the ash hole and internal horizontal channels.
The doors are attached using wire, which is twisted onto the ears of the cast iron elements and then placed into the masonry seams.

Third row almost completely repeats the configuration of the second, but taking into account the placement in the dressing. Therefore, it will also require 44 bars.

Fourth row. At this stage, the chimneys running inside the stove are blocked with a continuous layer of brick.
A firebox opening is left and a channel is formed that will heat the hob and discharge combustion products into the chimney.

In addition, a rotating horizontal chimney is blocked from above, discharging heated air under the stove bench.
To lay the level you need to prepare 59 bars.

Fifth row. The next step is to cover the kiln ledge with a second cross layer of brick. The smoke exhaust ducts and firebox continue to be removed. To work you need 60 bars.

Sixth row. The first level of the headrest of the couch is laid out and the part of the stove on which the hob will be installed begins to rise. Smoke exhaust ducts are still being removed. During the work you will need 17 bricks.

Seventh level. The laying of the headrest is completed, for which obliquely cut bars are used. The second row of the base is raised under hob. At this stage you will need 18 bricks.

Eighth level. The furnace structure with three channels is being laid. To do this you will need 14 bars.

Ninth and tenth rows similar to the previous one. They are laid out in the same way: alternately and in a dressing.
For each level you will need 14 bars.

Eleventhrow. Laying continues according to the scheme. To work you need to use 13 bricks.

Twelfth level. At this stage, a hole is formed for installing the chimney. The opening supplied under the stove is equipped with a block cut obliquely for a smoother flow of heated air into the adjacent channel leading to the lower horizontal pipes located in the stove bench. 11 bricks are used to lay the level.

Thirteenth row. A base for the slab is formed, and the central and side channels are combined. It is through them that hot air will flow under the stove, and then flow into the vertical channel leading under the stove bench.
10 bricks are laid.

On the 13th row, the foundation for the construction of the hob is prepared. To do this, a heat-resistant material, asbestos, is laid around the perimeter of the space in which two vertical channels were combined. A solid metal plate is placed on it.

Fourteenth row. The hole for the pipe is blocked and the wall is raised, separating the hob from the bench area. To work you will need only 5 bars.

Fifteenth row. To complete this level that raises the wall, 5 bricks are also needed.

The picture diagram shows an example of using a hob. In this case, the pan is placed exactly on that part of the surface that will warm up first, since a hot air flow passes under it.

After completing all the work described in the order, a chimney is installed in the hole located behind the stove, which is led out to the street.

From the back, the design looks quite neat, so it can be installed either near the wall or in the middle of the room.

This stove is perfect for heating a country house. If the structure and chimney are decorated with finishing materials, such equipment can become an original and functional addition to any private home.

As you can see, the corner formed under the cutting shelf is very convenient for drying and storing firewood.

Jet device with a warm bed

One of the variations of such heating units is a rocket stove with a sleeping place. It is based on the same principle of pyrolysis. The difference lies in the design of the heat exchanger itself. The long channels of the device are made of non-flammable materials and are interconnected. This structure is placed under the plane of the bed.

The ledge itself is a surface made of clay, stone or brick, inside which hot air circulates through the channels of the heat exchanger. During operation of the jet stove, the gas obtained by pyrolysis moves through the pipes under the stove bench, gives off heat and is discharged through a chimney located outside. Its height reaches 3000-3500 mm.

The stove structure with a firebox is located near one of the edges of the stove bench. Often there is also a cooking surface, with which a homemade rocket stove can also be used for cooking.

The stone or clay surface of the couch is covered with a wooden flooring or a mat made of bamboo or straw. This is necessary for the comfort of the user, because the bed serves as a sleeping place at night, and as a seat during the day. The peoples of Asia traditionally used the rocket stove for eating, equipping the stove with a special low table.

It is important to note that this type of furnace device uses fuel resources quite economically. To heat the unit, an armful of medium-thick dry branches is enough. Due to the fact that a brick rocket stove retains heat for a long time, by heating it once in the evening, you can enjoy the created comfort all night long, without worrying about adding fuel again.

Basic firebox rules

The main requirement for the operation of a wood-burning jet stove, due to which maximum heat transfer is achieved, is preheating. Paper, sawdust or wood chips thrown into the firebox are suitable for this. After the structure has sufficiently warmed up, the characteristic sounds will subside or change in tone: this is a signal that you can proceed to laying the main fuel, which will quickly flare up from the heat received at the beginning of work.

You can control the operation of the furnace thanks to special dampers that regulate draft. Until the fuel burns completely, the door of the combustion chamber or ash pan must be kept open. When the flame burns well and the oven begins to hum, you can close the door. The sounds made by the furnace equipment will tell you what exactly needs to be done. If during the combustion process the flame begins to die out, then by slightly opening the damper, you can help the stove flare up with renewed vigor.

Various stoves are still very often used to heat buildings. They are suitable for baths or saunas, as well as a variety of outbuildings.

They can be intended to form full-fledged heating, which will highly efficient and reliable. As a rule, pipes are installed simultaneously with the stove, which allows the use of the design for heating several rooms at once.

What is a rocket stove?

A do-it-yourself rocket stove is considered a rather interesting option for any room. Its design is original and it fits as for a private home, and for the bath, as well as for other types of structures. When creating it with a contour, expensive materials are not required; the dimensions are selected depending on the dimensions of the heated room, but it is important in advance do correct drawing to obtain an efficient and durable device. If the correct and current scheme is used, then you can do it yourself high-quality indoor water heating.

Operating principle of the furnace

The rocket stove operates on two specific principles. They are borrowed from other popular stoves that are supposed to be used for heating. These two principles include:

• , consisting in afterburning wood gases that arise during fuel combustion;
• the principle of free passage of gases through various channels, available in the equipment.

If the most simple design, which will be used for cooking, then the second principle of operation applies, since it does not contain elements suitable for creating pyrolysis.

The direct combustion wood rocket stove, which is the simplest, is not used for heating, but is suitable for cooking food, it has small sizes , and pipes are used to form it. The design of the unit consists of a short pipe, which is a firebox. It is in it that the fuel is placed, and during its combustion, hot gases arise, rising upward and escaping.

Read also: Why does a potbelly stove smoke when the door is opened?

A special cut is made in the pipe where you can cook food, and such a device is suitable for the home that is used very rarely in winter time . This type of stove is not suitable for heating, but it is very easy to find old pipes to create one, and if you watch the training video, the work can be easily implemented independently.

For heating a house or bath it is best to use improved equipment. It is usually created from bricks and metal sheets, and pipes are also used. “Robinson” is complemented by a heat exchange device and special channels for gas removal. The oven is also equipped with a suitable circuit, high quality and reliable shirt.

Such long-lasting equipment is usually used to form water and high-quality heating, which can be used for a house with a large number of rooms of different sizes. A video showing the operating principle of this equipment can be found easy to find on the Internet.

What are the pros and cons of a stove?

The rocket stove has positive and negative parameters. The advantages include:

• installation of equipment for a house using bricks, pipes and metal are simple;
• the cost of long-term equipment will be low;
• the ability to do the work with your own hands, since there are no difficulties in the process of laying bricks, when working with a contour, when installing a pipe or other elements, also rarely have to deal with modifications;
• such a furnace can be used to create full water heating;
• the dimensions of the equipment may vary depending on the heated room;
• Efficiency is very high, and the water heater turns out to be durable and reliable:
• Loading fuel for heating rooms is quick and hassle-free.

Wood rocket the stove also has disadvantages, which include:

• for heating it is important to use high-quality and completely dry, otherwise it will not be possible to achieve the desired combustion;
• Robinson oven requires constant human presence and control for safety of use.

Read also: Making a mini potbelly stove

What needs to be done before the actual work?

Initially, all materials and equipment should be prepared, and also drawings. It is important to determine the size of the future equipment, as well as decide what the its design and other parameters.

If the oven will be used to create water heating, then it is necessary to prepare pipes of the required quantity and quality. For masonry, you need to use heat-resistant red brick, since then you will get a long-burning stove that will not be dangerous to use and will also last a long time.

The use of brick is justified only for creating a stationary oven. A metal barrel and pipes for the chimney, a water heater, fittings and some others are also purchased. consumables, thanks to which you will get a full-fledged oven for high-quality and uniform water heating of the building.

Since the rocket furnace will have a water circuit, it is important to decide whether a heat exchanger will be purchased for an already created furnace or whether it will be created to fit the dimensions of an existing device.

The process of creating a furnace

The formation of the Robinson furnace is considered simple process, however, it is best to preview several videos to accurately understand all the nuances. The work is carried out in the following stages:

• a hole of suitable depth and size is created in the floor, which is intended for installing a stove chimney with a contour;
• a metal barrel is placed that protrudes into as a special cap, and it should be coated with heat-resistant paint to create a durable structure that does not deteriorate during fuel combustion;
• installation of a foundation for a furnace from bricks with water circuit, and for this, formwork is initially installed, and two or more bricks are deepened, then reinforcement is laid on the bottom and bricks are laid around the perimeter, after which the base is poured;
• After preparing the foundation, you can begin laying a furnace with a long-term circuit, and for this it is important to constantly refer to available drawings;
• During laying, it is important to place a flange in the barrel, with which chimney will be connected, a tee of a suitable type is also installed, thanks to which the pipes will be cleaned;
• on the rising part water heating element is installed, to which pipes intended for water heating are connected;
• the base of the resulting rocket stove must be surrounded with sandbags, and all holes and gaps are covered with clay;
• connects chimney pipe the right size , on the ascending part of which a metal barrel is mounted;
• testing the functionality of a rocket furnace with a circuit designed for long burning, and if problems are detected, all problems are eliminated.

Let's say right away: the rocket stove is 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 a wonderful bed in your home without resorting to building a complex, expensive and bulky Russian or bell-type stove. Moreover, the very principle of the design of the rocket stove gives greater freedom to design and the manifestation of creative abilities.

Rocket stove - wood fuel device

But 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.
• "Oven on reverse jet thrust" Is the stove flying tail first, or what?
• “How will she blow through 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 firing 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 this really good stove shows all its advantages.

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 high temperature 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 stove there is no conversion of energy types into each other, therefore it is not an engine. The stove simply distributes potential thermal energy properly 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 is 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. There were a lot of Chinese living there in the villages back then; cultural revolution 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, 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 stove 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 along Central Asia without loss. 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 with caution, but not at all because of inches-millimeters, liters-gallons and the intricacies 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 afraid the average citizen of the greatest empire in history is 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 corollary of the square-cube law is any specific design The furnace has a certain permissible range of its size and power, within which the specified parameters are ensured.

Why, for example, can’t you make a potbelly stove the size of a refrigerator and with a power of about 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.

Original drawing of a mobile rocket oven

The fact that the exact type of fire clay is not indicated here will be sorted out by ours. 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 only eats 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 survivalists needed a stove to heat the house, working 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 conditions: 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 must 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 nevertheless taken as a basis; the high efficiency achieved was very attractive in simple ways. But in attempts to make “long stoves” work on bad fuel, another circumstance became clear.

What is wood gas?

The high efficiency of long-burning furnaces 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 in this case– to the fundamentals of thermodynamics. Survivors do not suffer from sick pride; they turned to the basics. And they found the main operating principle of their furnace, which has no analogues in others: slow adiabatic afterburning of pyrolysis gases in a weak 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 excessive so that cold air did 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.

Construction of rocket furnaces

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 pipelines with an upward 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 bit 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 upward-extended 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: the secondary cleaning will have to be opened once or twice a year, so you don’t have to bother with the hinges. 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 oven on the same principle continuous burning for cooking in warm time year. During the heating season, a drum cover (Optional Cooking Surface) is suitable for cooking. large oven, 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. You can't do that in a big oven. fine adjustment 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 revolutionizes the classroom camping stoves, especially tourists. 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 stove 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 have a common property: they need to be launched only onto a 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 starts 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 gets 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. Firstly, this 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, dimensions 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:

1. Drum height H – 1.5-2D.
2. Drum coating height – 2/3H; For the sake of design, the edge of the coating can be made oblique and curved, then 2/3H must be maintained on average.
3. The thickness of the drum coating is 1/3D.
4. Riser cross-sectional area – 4.5-6.5% of S; It's better to stay within 5-6% of S.
5. 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.
6. The length of the flame tube is equal to the height of the riser.
7. 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.
8. 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.
9. 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.
10. The cross-sectional area of ​​the external chimney is 1.5-2S.
11. 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.
12. The height of the coating of the stove bench 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.
13. The height of the external chimney is from 4 m.
14. 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 bungalow bench 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 according to 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.

Schemes of riser lining in rocket furnaces

For what? Firstly, the requirements for the external chimney are reduced, because The external rod now pulls better. And since it pulls better, then permissible length The hog in the bed falls slower 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 is half as long - 4 m.

How to line with sand?

If the riser lining is fireclay, then the residual cavities are simply filled in 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 from a gas cylinder: 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.

Drawings of a rocket stove from a gas cylinder

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 furnace 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

Diagram of a rocket stove made from cans

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 wet 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. Welded from steel sheet a rocket stove (right position) with sand insulation is twice as light and economical as a potbelly stove of the same power.

Compact rocket stoves

Brick

Rocket stove made from broken bricks

We will not talk about large stationary rocket furnaces: in them all the original thermodynamics are in tatters, 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 stove made of 16 bricks (eng)

New material

Diagram of the Shirokov-Khramtsov furnace

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 modern material– heat-resistant concrete, adjusting all 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 like 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 bathhouse. To get light steam, the sauna stove must immediately warm up the walls with thermal (IR) radiation, and then, 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. Published

P.S. And remember, just by changing your consciousness, we are changing the world together! © econet

You can make a rocket furnace yourself using ordinary steel. The rocket stove is commonly known around the world as heating design long burning on solid fuel. To achieve maximum efficiency we had to work hard. A liquid fuel stove can release all its energy, but wood is more difficult to process. To unlock the full potential of wood, jet kilns were equipped with a chamber for afterburning gases.

• • Operating principle of a long-burning rocket stove
  • DIY rocket stove: advantages, drawings, disadvantages
  • Drawings of a jet stove from a gas cylinder and other types
  • DIY drawings of the Flint stove and other models
  • DIY jet stove assembly for heating
  • Improved rocket furnace with water circuit
  • DIY rocket stove drawings (video)
  • Examples of a rocket stove (photo of ideas)

The Shirokov-Khramtsov rocket or jet stove did not get its name because of its connection with space. The point is the shape of the device and the noise that is created during operation, reminiscent of the operation of a rocket. But this sound indicates improper use of the oven.

Types of long-burning rocket stoves:

• Portable (mobile);
• Stationary (for heating).

The most popular rocket model is Robinson. It is often used on hikes. Thanks to a small portable device, you can understand the principle of operation of jet furnaces. The shape of the oven resembles the letter “L”.

If the furnace is too noisy and buzzes during operation, then this mode is ineffective and expensive. Normally there should be a quiet sound, a little rustling.

The reaction furnace has a receiving hopper. This is the horizontal part of the pipe. A draft arises in the channel itself, it is this that affects the intensity of combustion, warming up the body. This is why it is advisable to limit the oxygen supply. Otherwise, the wood will quickly burn and all the heat will disappear.

A long-burning rocket stove is often used for heating garages and utility rooms

The stove operates on jet traction due to the natural flow of hot air. The higher the temperature of the firebox walls, the better the wood burns. This allows you to quickly heat water in large capacity, which is indispensable on a road trip. If you equip the pipe with thermal insulation, then after warming up you can burn thick logs.

DIY rocket stove: advantages, drawings, disadvantages

If desired, the conventional design of the furnace can be improved. This is how a potbelly stove loses a lot of heat, but by equipping the device with a water circuit or brickwork, these problems can be solved. Drawings are made for all these manipulations.

Advantages of jet furnaces:

1. Simple and inexpensive design. You can use available materials without significant financial costs. All work can be done with your own hands; no special knowledge or skills are required.
2. You can control the combustion yourself by choosing the desired intensity.
3. High efficiency. In general, everything depends on the quality of installation. The main thing is to extract maximum energy from the flue gases.

But such a simple and convenient design also has significant disadvantages. So you need to select special fuel for the stove. Do not use wet firewood, otherwise pyrolysis will not occur. The firebox may begin to smoke profusely, and all the gases will be directed into the house. In addition, a rocket stove requires increased safety requirements.

The most popular portable model is the Robinson rocket stove. It was modified and a grate was added.

Homemade jet stoves are not used for heating baths. They are ineffective in infrared light, which plays an important role for a steam room. Surface structures have small area heating, so they cannot heat the bathhouse.

Drawings of a jet stove from a gas cylinder and other types

Long-burning stoves are divided into stationary and mobile. Mobile ovens used on hikes, picnics, and outdoors for heating and cooking. Stationary ones are used for heating a house, outbuildings, greenhouses, and garages. There are 4 types of structures.

Types of reactive furnaces:

• Homemade camp stove from metal pipes, buckets, cans;
• Jet design from a gas cylinder;
• Brick oven with metal container;
• Stove with a stove bench.

Drawings of a jet stove from a gas cylinder can be downloaded on the Internet or made by hand yourself

The portable structure is equipped with pipe sections. The only difference concerns the installed partition for the ash pan. For the lower part, a grate can be used.

A device made from a gas cylinder is more difficult to build, but significantly increases efficiency. To install the structure you need a barrel or gas cylinder. Firewood in the firebox burns due to the influx of oxygen by loading it through a special window.

The gases burn out in the pipe, which is located inside the structure, due to the supply of secondary air. The effect is enhanced by insulation inner chamber. Hot air is placed in the hood, and then into the outer chamber. Combustion products are removed through the chimney.

To create draft, the top of the chimney is placed 4 cm above the loading window.

The combined model made of brick and metal is a stationary structure. Due to its high heat capacity, a wood stove accumulates and releases heat over several hours. That is why residential premises are heated with this design.

The rocket unit with a stove bench is an improved device that can retain heat longer. Since some of the heat escapes through the chimney, we increased its length. Due to the rapid excision of hot gases and a larger smoke outlet, this problem was solved.

This creates massive stoves with a bench that look like a sofa or bed. This stationary devices made of brick or stone. Thanks to its unique design, the stove is able to retain heat all night.

DIY drawings of the Flint stove and other models

It is best to make small portable structures with your own hands: the “Ognivo” and “Robinson” rockets. It is easy to perform the calculation, and the work will require cutting of profile pipes and metal welding skills. Dimensions may differ from the drawing, that's okay. It is important to maintain proportions.

To increase the combustion intensity, it is recommended to add improvised nozzles to the design. Secondary air for afterburning will flow there.

Stationary rocket stoves are made from a gas cylinder or metal barrel. These elements act as a body. Inside, the stove is equipped with smaller pipes or fireclay bricks. From a cylinder you can make both a stationary unit and a mobile one.

Continuous combustion furnace diagram:

• Chimney;
• Cap;
• Insulation;
• Loading hopper;
• Combustion zone;
• Afterburning zone.

The Ognevo stove can be bought in a specialized store at a fairly reasonable price.

Calculating a rocket stove can be difficult, because there is no exact method. You should pay attention to proven finished drawings. It is necessary to determine the size of heating equipment for a specific room.

DIY jet stove assembly for heating

Construction of the furnace begins with preparatory work. First you need to decide on the place of construction. It is chosen based on the requirements that relate to solid fuel structures: wood or coal.

Once the location has been decided, it is necessary to properly prepare it for construction. Wooden floor under the stove is dismantled. They dig a small pit and compact the bottom.

In a small room, the jet stove is placed in the corner. The loading hopper occupies one side and the deck chair occupies the other.

The barrel or cylinder also needs to be prepared for installation. To do this, cut off the lid and tap. Then the structure is cleaned. Next, prepare the solution.

Stages of construction of a jet stove with a stove bench:

1. The bottom of the dug hole is lined with fireclay bricks. Formwork is made along the contour of the recess. Reinforcement is performed.
2. Lay out the base and fill it with concrete. A day later, when the concrete has hardened, further work begins.
3. From fireclay bricks lay out the base of the stove. The side walls are raised and a lower channel is made.
4. The combustion chamber is covered with brick. There are two holes left on the sides. One is for the firebox, the second is for the vertical pipe (riser).
5. The metal body is equipped with a flange into which the horizontal channel of the stove will flow. All seams must be airtight and well sealed.
6. TO horizontal pipe attach a side outlet, which serves as an ash pan.
7. A fire tube is made from brick. As a rule, it is square.
8. The flame tube is equipped with a casing. The gaps are filled with perlite.
9. The installation of the cap is done from a cut-off part of a barrel or cylinder. It is equipped with a handle.
10. Equip the furnace body with brick or stone.
11. Equip the front part of the stove. Lay out the required contour.
12. A prepared barrel is placed on the base. The lower part must be sealed with clay.
13. Using a corrugated pipe, a channel is formed connecting the firebox to the street.
14. The heat exchanger pipes are connected to the lower pipe.
15. Installing a chimney. All elements must be sealed using asbestos cord and fire-resistant coating.

To properly assemble a jet stove with your own hands, you should first watch a training video and study the recommendations of specialists

Improved rocket furnace with water circuit

A long-burning boiler can be obtained by equipping the stove with a water jacket. Water heating may not be efficient enough. The fact is that the bulk of the warm air enters the room and containers on the cooking surfaces. To create a rocket boiler, you need to give up the possibility of cooking on the stove.

Materials required for equipping a stove with a water circuit:

1. Fireclay bricks and mortar for masonry;
2. Steel pipe (diameter 7 cm);
3. Barrel or cylinder;
4. Insulation;
5. Sheet steel and a barrel of smaller diameter than for the body to create a water jacket;
6. Chimney (diameter 10 cm);
7. Parts for the heat accumulator (tank, pipes, connecting pipe).

A characteristic feature of rocket furnaces with a water circuit is that the vertical part is insulated to ensure combustion of pyrolysis gases. In this case, warm air is directed into a coil with a water circuit and transfers heat to the stove. Even when all the fuel has burned out, in heating circuit Warm air will still be supplied.

DIY rocket stove drawings (video)

Jet stoves are widely known among people. Even Korea, China, England and the population of Japan used them. The Chinese stove differed from others in its ability to heat the entire floor. But the Russian analogue is in no way inferior. Thanks to useful innovations, the stove can hold heat for a long time.

Examples of a rocket stove (photo of ideas)

Jet stoves have become popular not so long ago. In addition, not everyone knows about the advantages of such a heating system. It is worth noting that they are classified as energy efficient stoves. Such heating systems received their name due to reactive processes based precisely on heat exchange under significant temperature differences. In this case, draft occurs in the reaction furnace. A similar phenomenon is described in the basic physics course. And this is thanks to trouble-free operation.

Design of the Raketa stove

The reaction furnace is always equipped with an elbow, the angle of which is no more than ninety degrees. This is the main feature of this model. In other words, the chimney is located at an acute or right angle in relation to the bottom of the firebox. In this case, the oven must be equipped with an air duct. It is usually placed through the wall with the firebox.

Advantages of reactive furnaces and their operating principle

Before you build a jet stove with your own hands, it is worth understanding the principle of its operation and evaluating its advantages. The main difference between this design is that the temperature concentration occurs precisely in the air flow, which is constantly in motion, and not in the firebox. In this case, continuous traction occurs in the knee - at the place of heating. Air with oxygen for combustion is supplied through the duct, and in the firebox it receives a sufficient amount of thermal energy. In this case, ordinary wood can be used as fuel. In places where there is a temperature difference, it is given off. In this way, traction is constantly maintained.

A jet furnace in constant mode does not require special adjustment of the air supply. After all, the natural balance of all processes provides the necessary traction. In other words, the one that is required to maintain the desired temperature in the firebox. As for the release of all exhaust gases, this process also occurs naturally, using the pressure of already heated air. It is for this reason that a jet stove is built with a low chimney.

First stage of construction: flows only in their pure form

A jet furnace, the circuit of which is not so complicated, consists of several important elements. One of them is the knee. To make it, you can weld two pipes at right angles. These parts must be at least fifteen centimeters in diameter. In this case, the ratio of 1 to 2 must be observed. The result should be already finished firebox with a chimney pipe. The short part of the knee should be horizontal, and the long part vertical. If you light a fire in a chimney, the heat will go up.

To organize the supply of secondary air, you can use one of the primitive options. To do this, install on the brackets inside the firebox metal sheet. This will allow you to move the source away from the air duct. But the air that passes through it will always end up in the corner of the knee. This is what allows us to call it secondary. To make a self-made jet stove more functional, you can weld the legs to the finished device and install a grate for the frying pan on the upper channel.

Second stage of construction: “rocket” potbelly stove

The basis is the structure built in the first stage. One more important element needs to be added to it - a horizontal section. The rectangular cross-section of channels is much more convenient in terms of operation than pipes. A jet furnace, the drawings of which allow you to more accurately imagine the entire structure, can have a different structure. In this case, the air duct can be positioned arbitrarily. However, it is worth observing one of the rules. In any case, air must flow through the duct. To do this, you can use plates on the ribs along the bottom wall, parallel side walls of the loading hatch or “brushes”.

After this, the steel chimney is attached to the elbow. Then you can install the roof. It is very difficult to describe this design exactly. After all, for its manufacture they usually use all kinds of available materials. A jet stove is often made from a gas cylinder. The main thing is that the principle of flow formation is implemented.

Third stage of construction: design with vertical heat exchanger

This idea consists of creating a heat exchanger made of steel with sufficiently thick walls precisely along the path of heat flow. The element built in the second stage must be increased in size. To do this, you need to install an empty container instead of a pipe running vertically, which will be used for dry heat exchange. In this case, a gas cylinder is ideal.

The jet stove must be built in such a way that the horizontal element is located coaxially with the chimney duct. This point is very important. In this case, the firebox - a horizontal element - can be made in several versions. This could be a box, a pipe, or a stove body. If this part is of sufficient size, it can be used as a preliminary heat exchanger.

In order for the jet stove, the diagram of which is presented above, to burn continuously for up to 4 hours, the fuel compartment must be increased in size. This element can be up to 60 centimeters in height. In this case, the loading of logs must be vertical. In such a situation, combustion of raw materials will occur in the lower part. The logs will gradually burn and sink lower under their own weight.

The Shirokova jet furnace is quite simple in design. Primary air is usually supplied through a door located in the firebox area, and secondary air is supplied through a duct or hole in the elbow.

The fourth stage of construction: installation of the injector

At this stage, it is necessary to equip the product with a separate channel, through which oxygen will flow during the fuel combustion stage. This requires a pipe with a diameter of 1.2-1.5 centimeters, preferably curved in the shape of the channel itself, made from individual structural elements. A plug should be installed on one side and up to eight holes with a diameter of six millimeters should be made in one of the walls. The area with holes made should be no more than 100 millimeters in length. The finished pipe must be installed in such a way that it passes through the entire system. In this case, the edge with the plug should reach the place where the flame can still reach. As for the open side, it should be in the cold part of the structure and have a flow of fresh air. When heated, the metal will create the necessary traction.

Fifth stage of construction: installation of turbocharging

The reaction furnace is not yet finished at this stage. An air pump should be connected to the injector. For these purposes, you can use a regular old vacuum cleaner. In this case, the injector must have sufficient throughput. After the pump is turned on, not only will the flow of fresh air increase, but also additional draft will be created. At the same time, the draft will increase in proportion to the power supplied. This process will be ensured by increasing the temperature in the heat exchanger.

It is worth noting that this method has been known for a long time. It was used by masters. In this case, the functions of the air pump were performed by a special blacksmith's bellows.

Instead of a conclusion

If you are interested in a jet stove and you decide to install it in your home, remember a few main rules. First of all, every detail in the system must be harmonious. Each piece of the structure must be balanced. Otherwise, overheating will occur, which will ultimately lead to burnout of metal parts. It is worth noting that the jet stove should be installed not near the wall, but at some distance from it. This way it will heat the room more efficiently.