Engine Stirling Disadvantages. External combustion engine can be made from tin can. The design of the execution "Alpha"

External combustion engines began to be used when people needed a powerful and economical source of energy. Prior to that, steam installations were used, but they were explosive, since they used hot steam under pressure. In the early 19th century, they received devices with external combustion, and after another tens of years, already familiar devices with internal combustion were invented.

Origin of devices

In the 19th century, humanity faced the problem, which was that the steam boilers were too often exploded, and also had serious constructive flaws, which made their use undesirable. The output was found in 1816 by the Scottish priest Robert Stirling. These devices can also be called "hot air engines", which were still applied in the 17th century, but this man added a cleaner called the regenerator currently called the invention. Thus, the engine external combustion engine was able to greatly increase the performance of the installation, as it retained heat in the warm working area, while the working fluid was cooled. Because of this, the efficiency of the entire system was significantly increased.

At that time, the invention was used quite widely and was on the rise of its popularity, but over time it was stopped using it, and they forgot about him. Steam installations and engines, but already familiar, with internal combustion, came to replace the equipment of external combustion. Again, they remembered only in the 20th century.

Installation work

The principle of operation of an external combustion engine is that it constantly alternates two stages: heating and cooling of the working fluid in a closed space and energy obtaining. This energy arises due to the fact that the volume of the working fluid is constantly changing.

Most often, the working substance in such devices becomes air, but it is possible to use a helium or hydrogen. At that time, the invention was at the development stage, such substances as nitrogen dioxide, freons, liquefied propane-butane were used as experiments. In some samples, they tried to apply even ordinary water. It is worth noting that the external combustion engine, which was launched with water as a working substance, was distinguished by the fact that he had a fairly high specific power, high pressure, and he was quite compact.

The first type of engine. "Alpha"

The first model that was used, became Alpha Stirling. The peculiarity of its design is that it has two power pistons located in different in separate cylinders. One of them had a sufficiently high temperature and was hot, the other, on the contrary, cold. Inside the heat exchanger with a high temperature there was a hot pair of cylinder-piston. Cold steam was inside the heat exchanger with low temperatures.

The main advantages of the thermal engine of external combustion was the fact that they had high power and volume. However, the temperature of the hot pair at the same time was too large. Because of this, some technical difficulties arose in the process of manufacturing such inventions. The regenerator of this device is between hot and cold connecting tubes.

Second sample. "Beta"

The second sample was the Beta Stirling model. The main constructive difference was that there was only one cylinder. One of his ends served as a hot pair, and the other end remained cold. Inside this cylinder, the piston was moved from which the power can be removed. Also inside there was a displacer, which was responsible for changing the volume of the hot work area. In this equipment, gas was used, which was pumped from a cold zone to hot through the regenerator. This type of external combustion engine possessed a regenerator in the form of an external heat exchanger or combined with the piston-displacer.

Latest model. "Gamma"

Last species this engine Steel "Gamma" Stirling. This type differed not only by the presence of the piston, as well as the displacer, and also the fact that two cylinders were already in its design. As in the first case, one of them was cold and it was used to take power. But the second cylinder, as in the previous case, was cold from one end and hot from the other. Here displaced the displacer. IN piston Engine External combustion also had a regenerator who could be two types. In the first case, it was external and connected together such structural parts as a hot cylinder zone with cold, as well as with the first cylinder. The second type is an internal regenerator. If this option was used, it was included in the design of the displacer.

The use of stirlings is justified if a simple and small thermal energy converter is needed. It can also be used if the temperature difference is not high enough to use gas or steam turbines. It is worth noting that today such samples began to be used more often. For example, autonomous models for tourists are used, which are capable of working from gas burner.

Application of devices at present

It would seem that such an old invention cannot be used in our days, but it is not. NASA ordered an external combustion engine of the Stirling type, but nuclear and radioisotope heat sources should be used as a working substance. In addition, it can also be successfully used for the following purposes:

• Use such an engine model to pump liquid is much easier than the usual pump. In many ways, this is due to the fact that the piston can be used the pumped liquid itself. In addition, it will cool the working body. For example, this kind of "pump" can be used to pump water into irrigation channels using solar heat for this.
• Some manufacturers of refrigerators are inclined to install such devices. The cost of products will be able to reduce, and as refrigerant can be used ordinary air.
• If you combine the external combustion engine of this type with the heat pump, you can optimize the operation of the thermal network in the house.
• Pretty successfully stirlings are used on submarines of the Navy Sweden. The fact is that the engine works on liquid oxygen, which is subsequently used for breathing. For a submarine, this is very important. In addition, such equipment has a fairly low noise level. Of course, the unit is large enough and requires cooling, but it is these two factors that are insignificant if we are talking about a submarine.

Advantages of using the engine

If during the design and assembly, we will apply modern methods, then it will be possible to raise the coefficient useful action External combustion engine up to 70%. The use of such samples is accompanied by the following positive qualities:

• Surprisingly, the torque in this invention is almost independent of the rotation speed of the crankshaft.
• In this force unit, there are no elements such as the ignition system and the valve system. There is also no camshaft here.
• It is quite convenient that throughout the period of use, it will not be necessary to adjust the equipment and configure equipment.
• Engine model data is not able to "stall". The simplest design of the device allows you to use it quite a long time in a fully offline mode.
• You can use almost everything from the firewood and ending with uranium fuel as a source of energy.
• Naturally, in the external combustion engine, the burning process of substances is carried out outside. This contributes to the fact that the fuel is in full, and the amount of toxic emissions is minimized.

disadvantages

Naturally, any invention is not devotioned. If we talk about the minuses of such engines, then they are as follows:

1. Due to the fact that the combustion is carried out outside the engine, the removal of the resulting heat occurs through the walls of the radiator. This forces to increase the dimensions of the device.
2. Material consumption. In order to create a compact and efficient engine model Stirling, it is necessary to have high-quality heat-resistant steel that can withstand a large pressure and high temperature. In addition, there must be low thermal conductivity.
3. As a lubricant will have to buy special toolsince the usual cocks when high temperatureswhich are achieved in the engine.
4. To obtain a sufficiently high specific power, it is necessary to use either hydrogen or helium as a working substance.

Hydrogen and helium as fuel

Obtaining high powerOf course, it is necessary, however, it is necessary to understand that the use of hydrogen or helium is quite dangerous. Hydrogen, for example, itself is sufficiently explosive, and at high temperatures it creates connections called metalhydrites. This happens when hydrogen is dissolved in the metal. In other words, it is able to destroy the cylinder from the inside.

In addition, hydrogen, and helium are volatile substances that are characterized by a high penetrating ability. If it is easier to speak, then they are easily seeping through almost any seals. And the loss of the substance means losses in the operating pressure.

Rotary external combustion engine

The heart of such a car is a rotary expansion machine. For engines S. external type Combustion This element is represented in the form of a hollow cylinder, which is covered with covers on both sides. By itself, the rotor has the appearance of the wheel, which is planted on the shaft. It also has a certain amount of P-shaped extended plates. For their extension, a special retractable device is used.

External combustion engine Lukyanova

Yuri Lukyanov is a researcher of the Pskov Polytechnic Institute. He has long been developing new models of engines. The scientist tried to make such elements such as the gearbox, camshaft and exhaust pipe in the new models. The main disadvantage of Stirling devices was that they had too large dimensions. It was this lack of a scientist and managed to eliminate due to the fact that the blades were replaced by pistons. It helped to reduce the size of the entire design several times. Some suggest that you can make an external combustion engine with your own hands.

Just about a hundred years ago engines internal combustion I had to conquer the place that they occupy in modern automotive in a cruel competitive struggle. Then their superiority did not seem so obvious as today. Indeed, Steam Machine - Main Rival gasoline motor - possessed compared to him with huge advantages: silent, simplicity of power regulation, beautiful traction characteristics and amazing "omnivorous", allowing to work on any form of fuel from firewood to gasoline. But ultimately, the economy, ease and reliability of internal combustion engines took over and forced to reconcile with their disadvantages, as inevitability.
In the 1950s, with the advent of gas turbines and rotary engines, the assault storming of the monopoly position occupyed by the engines of internal combustion in the automotive industry, the assault, which was still not crowned with success. At about the same years, attempts were made to bring to the scene new enginein which the cost-effectiveness and reliability of the gasoline engine with silent and the "omnivorous" of the steam plant is strikingly combined. This is the famous external combustion engine that Scottish priest Robert Stirling patented on September 27, 1816 (English Patent No. 4081).

Process physics

The principle of action of all the thermal engines without exception is based on the expansion of the heated gas, a large mechanical work is performed than it is required to compress cold. To demonstrate this, enough bottles and two saucepans with hot and cold water. At first, the bottle is lowered into the ice water, and when the air is cooled in it, the neck is plugged with a plug and are rapid in hot water. After a few seconds, cotton is distributed and the gas heated in the bottle pushes the plug by making mechanical work. A bottle can be returned to ice water again - the cycle will repeat.
In the cylinders, pistons and intricate levers of the first stirling machine, this process was almost exactly reproduced, until the inventor realized that part of the heat was taken away from the gas during cooling, it can be used for partial heating. We need only some kind of container in which it would be possible to store heat taken from the gas during cooling, and again give it when heated.
But, alas, even this very important improvement was not saved by the stirling engine. By 1885, the results achieved here were very mediocre: 5-7 percent kp, 2 liters from. Power, 4 tons of weight and 21 cubic meters occupied space.
External combustion engines were not even saved by the success of another design developed by the Swedish Engineer Erickson. Unlike Stirling, he suggested heating and cooling the gas not at a constant volume, but at constant pressure. 8 1887 Several thousand small Ericson engines perfectly worked in printing houses, houses, in mines, on ships. They filled out water tanks, led the effect of elevators. Erickson tried to even adapt them to drive carriages, but they were too heavy. In Russia before the revolution, a large number of such engines were produced under the name "Heat and Strength".

One of the promising sources of mechanical energy for cars is an external combustion engine developed by the Scotland native Robert Stirling a couple of centuries ago. The engine of external combustion of Stirling on the principle of operation is very different from the usual for all. But for some time after the development, it was safely forgotten.

History of creation

In 1816, a native of Scotland Robert Stirling patented a thermal car, which is called in honor of its creator. However, the idea of \u200b\u200bhot air engines itself was invented not at all. But the first conscious project to create such an aggregate was implemented precisely Stirling.

He improved the system by adding a cleaner into her, in the technical literature called the heat exchanger. Due to this, the performance of the motor has increased due to keeping it warm. This model for that time was recognized as the most durable, since never exploded.

Despite such a rapid success of the promotion of the model, at the beginning of the twentieth century, from the further development of the external combustion engine, due to its cost in favor of the internal combustion engine.

Stirling engine: principle of operation and modification

The principle of operation of any thermal motor is that there are consistent mechanical efforts to obtain gas in an extended state. As a visual example, you can deal with two saucepans, according to which they are filled with cold and hot water. Lower in cold water a bottle with a swirling cork. After that, the bottle is transferred to hot water.

With this movement, the gas in the bottle performs mechanical work and pushes a cork from the neck. The first model of the external combustion engine worked at exactly the same principle. However, later the creator realized that part of the heat released can be used to heal. The productivity of the unit has only increased from it.

A little later, the engineer from Sweden Erickson has improved the design by putting forward an idea of \u200b\u200bcooling and heating the gas at constant pressure instead of volume. This allowed the engine to "move through the career staircase" and start used in mines and printing houses. For the crews I. vehicle The aggregate was too heavy.

The figure shows the operating cycle of the stirling engine.

How does the stirling engine work? It converts thermal energy, summing out from outside, into useful mechanical work. This process occurs due to changes in the temperature of the gas or fluid circulating in the closed volume. At the bottom of the unit, the working substance is heated, increases in the volume and pushes the piston up.

Hot air enters the upper part of the motor and cooled with a radiator. The pressure of the working flu is reduced, and the piston is lowered to repeat the entire cycle. The system is completely sealed, so the working substance is not spent, but only moves inside the cycle.

In addition, there are motors with an open cycle in which the flow control is implemented using valves. These models are called Erixon's engine. In general, the principle of operation of an external combustion engine is similar to the engine. For low temperatures It is compressed in it and vice versa. The heating is carried out in different ways.

Heat in an external combustion engine is supplied through the wall of the cylinder from the outside. Stirling guessed to apply a periodic change in temperature with a displacement piston. This piston moves gases from one cylinder cavity to another. At the same time, on the one hand, low temperatures are constantly maintained, and on the other - high. When the piston is moved up, the gas moves from a hot cavity.

The displacer system in the engine is connected to the working piston, which compresses the gas in the cold and allows you to expand warm. Useful work is performed just due to compression at lower temperatures. Continuity is ensured by a crank-connecting mechanism. Special boundaries between the cycle stages are not observed. Thanks to this, the efficiency of the stirling engine does not decrease.

Some engine work details

In the theory, any source of heat (sun, electricity, fuel) can input into the external combustion engine. The principle of engine body operation is to use helium, hydrogen or air. The thermal maximum possible efficiency has the ideal cycle. The efficiency is from 30 to 40%. Effective regenerator can provide more high efficiency. Built-in heat exchangers provide regeneration, exchange and cooling in modern engines. Their advantage is work without oils. In general, the grease engine needs a bit. The average pressure in the cylinder varies from 10 to 20 MPa. A good sealing system is needed and the possibility of oil getting into working cavities.

According to theoretical calculations, the efficiency of the stirling engine is strongly dependent on temperature and can achieve even 70%. The most first engine samples implemented in the metal have low efficiency, since the coolant variants were ineffective and limited the maximum heating temperature, there were no structural materials resistant to high pressure. In the second half of the 20th century, the engine with a rhombic drive during tests exceeded an indicator of 35% efficiency on aqueous heat carrier and with a temperature of 55 degrees Celsius. Improving the design in some experimental samples made it possible to achieve almost 39% of the efficiency. Almost all modern gasoline engineshaving similar power, possess the efficiency of 28 - 30%. Turbated diesel engines reach about 35%. The most modern samples of stirling engines developed by Mechanical Technology Inc in the United States show efficiency up to 43%.

After the development of heat-resistant ceramics and other innovative materials, it will be possible to increase the temperature of the medium even more. The efficiency can achieve even 60% under such conditions.

There are several modifications of the engine of the external combustion of Stirling.

Modification "Alpha"

Such an engine consists of hot and cold separate power pistons located in their own cylinders. It is warm to the cylinder with a hot piston, and the cold is located in the cooling heat exchanger.

Modification "Beta"

In this embodiment, the cylinder in which the piston is located, on the one hand heats up, and the other is cooled. Inside the cylinder moves the displacer and power piston. The displacer is designed to change the volume of the working gas. The regenerator also performs the return of the cooled working substance into the heated cavity of the engine.

Modification "Gamma"

All simple design modifications "Gamma" is made of two cylinders. The first one is completely cold. It makes the movement of the power piston. And the second is cold only on the one hand, and on the other - heated. It serves to move the mechanism of the displacer. Cold gas circulation regenerator in this modification can be common to both cylinders and be included in the displacer design.

Advantages of the engine of external combustion

This type of engine is unpretentious in terms of fuel, since the basis of its work is the temperature difference. What caused this difference - does not matter much importance. Stirling engine has a simple design and does not need additional systems and hinged equipment (Starter, gearbox). Some features of the engine device are a guarantee of a long service life: the engine can work continuously during approximately one hundred thousand hours. Another serious advantage of the external combustion engine is silent. It is due to the fact that there is no detonation in the cylinders and there is no need to withdraw the exhaust gases. The "beta" modification is especially allocated to this parameter. Its design is equipped with a diamond-shaped crank-rod mechanism, which provides the lack of vibrations during operation. And finally, environmental friendliness. In the engine cylinders there are no processes that can negatively influence the environment.

When choosing alternative heat sources (energy of the Sun), the stirling engine turns into a kind of environmentally friendly power aggregate.

Disadvantages of the engine of external combustion

The mass production of such engines is currently impossible. The main problem is the material consonant material. Cooling the engine's working fluid requires the installation of radiators with large volumes. As a result, the size increases. The use of complex working bodies like hydrogen or helium raises the issue of engine safety. Thermal conductivity and temperature resistance should be on high level. Heat to the working volume comes through heat exchangers. Thus, part of the heat is lost on the road. In the manufacture of heat exchangers have to use heat-resistant metals. At the same time, metals should be resistant to high pressure. All these materials are expensive and are processed long. The principles of changing the modes of an external combustion engine are very different from the traditional. Development of special control devices. Changing the power is caused by a change in pressure in the cylinders and the phase angle between the displacer and the power piston. You can also change the cavity capacity with the working fluid.

Examples of external combustion engines on vehicles

Workable models of such an engine were released, despite all the difficulties of manufacture. At the age of 50 of the 20th century, the automotive companies had an interest in this species of the force aggregate. Mostly implementing stirling engines on cars, Ford was engaged in Motor Company. and Volkswagen Group. The Swedish company United Stirling has developed such an engine in which the developers tried more often to use serial units and nodes (crankshaft, connecting rods). Four-cylinder was developed V-engine, having a specific weighing of 2.4 kg / kW. A compact diesel has a similar mass. The engine tried to install on the semitle cargo vans.

The most distinguished successful sample was the Philips 4-125DA, available for installation on cars. Engine operating capacity was 173 horse powers. The dimensions were unsolonged from the usual gasoline engine.

GENERAL MOTORS has developed an eight-cylinder V-shaped external combustion engine with a serial crank-connecting mechanism. In 1972, a limited version car Ford. Torino was equipped with such an engine. Moreover, fuel consumption decreased by as much as 25% compared with previous models. Today, several foreign companies are trying to improve the design of this engine in order to adapt for mass production and installation on passenger cars.

Pushed out other species power plantsHowever, work aimed at refusing to use these aggregates suggests the imminent change of leading positions.

Since the beginning of technical progress, when using motors burning fuel inside, it was not only obvious to their superiority. Steam engineAs a competitor, contains a lot of advantages: along with traction parameters, silent, omnivorous, easily controlled and configured. But lightness, reliability and efficiency allowed the internal combustion engine to take up the ferry.

Today, the head of the corner is issues of ecology, efficiency and security. It forces engineers to throw forces on serial units operating at the expense of renewable fuel sources. In the 16th year of the nineteenth century, Robert Stirling registered the engine operating from external sources Heat. Engineers believe that this unit is able to change the modern leader. Stirling engine combines economy, reliability, works quietly, on any fuel, it makes the product by a player in the automotive market.

Robert Stirling (1790-1878 years):

Stirling engine history

Initially, the installation was developed in order to replace the car operating at the expense of steam. The boilers of steam mechanisms exploded, with exceeding the permissible pressure standards. From this point of view, stirling is much safer, functions using the temperature difference.

The principle of operation of the stirling engine in alternate supply or selection of heat in a substance that work is performed. The substance itself is concluded in the volume of closed type. The role of the working substance is performed by gases or liquids. There are substances that perform the role of two components, the gas is transformed into a liquid and vice versa. Liquid stirling motor has: small dimensions, powerful, produces great pressure.

Reducing and increasing the volume of gas during cooling or heated, respectively, is confirmed by the law of thermodynamics, according to which all components: the degree of heating, the value of the space occupied by the substance, the force acting per unit area is associated and described by the formula:

P * V \u003d N * R * T

• P is the power of gas in the engine per unit area;
• V is a quantitative value occupied by gas in the engine space;
• n - molar amount of gas in the engine;
• R - permanent gas;
• T - the heating degree of gas in the engine to,

Stirling Engine Model:

Due to the unpretentiousness of the installations, the engines are divided: solid fuel, liquid fuel, solar energy, chemical reaction and other types of heating.

Cycle

The external combustion engine of stirling uses the same set of phenomena. The effect of the occurrence in the mechanism is high. Due to this, it is possible to construct an engine with good characteristics within normal dimensions.

It is necessary to take into account that in the design of the mechanism, the heater, refrigerator and regenerator, device, heat removal from the substance and heat return, at the right moment are provided.

The ideal cycle of Stirling, ("Temperature-volume" diagram):

Ideal circular phenomena:

• 1-2 change of linear dimensions of a substance with a constant temperature;
• 2-3 heat removal from the substance to the heat exchanger, the space occupied by the substance constantly;
• 3-4 Forced cutting of the space occupied by the substance, the temperature is constant, the heat is given to the cooler;
• 4-1 Forced increase in the temperature of the substance occupied by the space constantly, heat is summed from the heat exchanger.

The ideal cycle of Stirling, ("Pressure-volume" diagram):

From the calculation (mol) of the substance:

Favorite heat:

The cooling cooler is warm:

The heat exchanger gets heat (process 2-3), the heat exchanger gives the heat (process 4-1):

R is a universal permanent gas;

CV - ability perfect Gaza Hold heat with the unchanic size of the space occupied.

Due to the use of the regenerator, part of the heat remains, as the energy of the mechanism that does not vary for passing circular phenomena. The refrigerator gets less heat, therefore, the heat exchanger saves heat heater. This increases the installation efficiency.

KPD circular phenomena:

ɳ =

It is noteworthy that without heat exchanger, the set of stirling processes is feasible, but its effectiveness will be significantly lower. The passage of the totality of the processes is backwards leads to the description of the cooling mechanism. In this case, the presence of a regenerator, a prerequisite, since when passing (3-2-2), it is impossible to heat the substance from the cooler, the temperature of which is significantly lower. It is also impossible to give heat to the heater (1-4), the temperature of which is higher.

Principle of engine operation

To understand how the stirling engine works, let's understand in the device and the frequency of the aggregate phenomena. The mechanism converts heat obtained from the heater, which is outside the product into force of force on the body. The whole process occurs due to the temperature difference, in the working substance located in the closed circuit.

The principle of operation of the mechanism is based on expansion by heat. Improved directly, the substance in the closed circuit heats up. Accordingly, before cooled, the substance is cooled. The cylinder (1) is enveloped by a water jacket (3), heat is served for the bottom. The piston, making a job (4) placed in the sleeve and is sealed with rings. Between the piston and the bottom there is a displacement mechanism (2), having significant gaps and fluently moving. The substance in the closed loop moves through the volume of the camera due to the displacer. Movement of the substance is limited to two directions: bottom of the piston, bottom of the cylinder. The movement of the displacer provides a rod (5), which passes through the piston and functions due to the eccentric with a 90 ° delay in comparison with the piston drive.

• Position "A":

The piston is located in the extreme lower position, the substance is cooled due to the walls.

• Position "B":

The displacer occupies the upper position, moving, passes the substance through the end slots to the bottom, is cooled itself. Piston stands motionless.

• Position "C":

The substance gets heat, under the action of heat increases in the volume and raises the extender with the piston up. Work is performed, after which the displacer falls on the bottom, pushing the substance and cooling.

• Position "D":

The piston lowers down, compresses the cooled substance, useful work. The flywheel serves in the design of the energy battery.

The model considered without a regenerator, so the efficiency of the mechanism is not large. The heat of substances after the operation is discharged into the coolant, using the walls. The temperature does not have time to decline on the desired value, so cooling time is extended, the speed of the motor is small.

Types of engines

Constructively, there are several options using the principle of stirling, the main types are considered:

The design applies two different pistons placed in various contours. The first circuit is used for heating, the second circuit is used for cooling. Accordingly, each piston owns its regenerator (hot and cold). The device has a good power ratio to volume. The disadvantage is that the temperature of the hot regenerator creates structural difficulties.

• Engine "β - Stirling":

The design uses one closed circuit, with different temperatures at the ends (cold, hot). The cavity is the piston with the displacer. The displacer divides the space on the cold and hot zone. The exchange of cold and warmth occurs by pumping the substance through the heat exchanger. Structurally, the heat exchanger is performed in two versions: external, combined with the displacer.

• Engine "Γ - Stirling":

The piston mechanism provides for the use of two closed circuits: cold and with the displacer. Power is removed from a cold piston. The piston with the displacer on one side is hot, on the other side is cold. The heat exchanger is located both inside and outside the design.

Some power plants are not similar to the main types of engines:

• Rotary stirling engine.

Constructively invention with two rotors on the shaft. The part performs rotational movements in the closed space of the cylindrical shape. The synergistic approach to the implementation of the cycle is laid. The housing contains radial slots. In the recess inserted blades with a certain profile. Plates are on the rotor and can move along the axis when the mechanism is rotated. All items create changing volumes with phenomena performed in them. Volumes of various rotors are associated with channels. The location of the channels have a shift of 90 ° to each other. Rotor shift relative to each other is 180 °.

• Thermoacoustic stirling engine.

The engine uses acoustic resonance for processes. The principle is based on moving a substance between hot and cold cavity. The scheme reduces the number of moving parts, the complexity in removing the resulting power and maintain resonance. The design refers to free motor.

Stirling engine with his own hands

Today, quite often in the online store you can meet souvenir productsmade in the form of the engine under consideration. Constructively and technologically, the mechanisms are quite simple, if desired, the stirling engine is easy to construct with their own hands from the remedies. On the Internet you can find a large amount of materials: video, drawings, calculations and other information on this topic.

Low-tempered stirling engine:

• Consider the easiest option of the wave engine, to execute the canning bank, soft polyurethane foam, disc, bolts and stationery clips. All these materials are easy to find at home, the following actions remain:
• Take a soft polyurethane foam, cut two millimeters with a smaller diameter from the inner diameter of the conservation circle. The height of foam is two millimeters more than half the height of the jar. Foolon plays the role of the seizer in the engine;
• Take the lid of the bank, in the middle do the hole, the diameter is two millimeters. Squash to the hole hollow rod, which will perform the role of the engine rod guide;
• Take the circle cut out of the foam, insert into the middle of the circle of the screw and stroke on both sides. To the washer, solder the pre-straightened clip;
• In two centimeters from the center, drill holes, a diameter of three millimeters, the threads of the outstruder through the central hole of the cover, solder the lid to the bank;
• Make a small cylinder from a tin, a diameter of a centimeter one and a half, solder it to the lid of the cans in such a way that the side opening of the cover turned out to be clearly in the center inside the engine cylinder;
• Make the crankshaft of the engine from the clip. The calculation is performed in such a way that the knee variation was 90 °;
• Make the stack under the engine crankshaft. From the polyethylene film, make an elastic membrane, put on the film on the cylinder, sell it, lock;

• Independently make the engine connecting rod, one end of the straightened product will be in the form of a mug, insert the second end into the slice of the eraser. Length is adjusted in such a way that in the extreme lower point The mucker shaft was drawn, at the extreme top point, the membrane is pulled as much as possible. Set the other connecting rod for the same principle;
• Rubber tip rolling rod ride. Shutun without a rubber tip fasten on the displacer;
• Put on the crank mechanism of the engine flywheel from the disk. At the bank, make legs to keep the product in your hands. The height of the legs allows you to place a candle under the can.

After you managed to make the stirling engine at home, the motor is started. To do this, a lit candle is placed under the jar, and after the bank warmed up, give a push to the flywheel.

The considered installation option can be quickly collected at home as a visual allowance. If the goal and desire to make the stirling engine as close as possible to the factory analogues, there are drawings of all parts in free access. Step-by-step execution of each node will create a working layout of anything no worse than commercial versions.

Benefits

For the stirling engine, such advantages are characteristic:

• To work the engine, a temperature difference is needed, which fuel causes the heating is not important;
• No need to use attachments and accessories, the engine design is simple and reliable;
• The engine resource, due to the design features, is 100,000 hours of operation;
• Engine operation does not create foreign horsesbecause there is no detonation;
• The process of operation of the engine is not accompanied by emissions of spent substances;
• Engine operation is accompanied by minimal vibration;
• The processes in the installation cylinders are environmentally friendly. The use of the correct heat source allows you to make the engine "clean".

disadvantages

The disadvantages of the stirling engine belong:

• It is difficult to establish mass production, since a structurally engine requires the use of a large number of materials;
• High weight and large engine dimensions, because for efficient cooling it is necessary to use a large radiator;
• To increase efficiency, the engine is forced, applying complex substances (hydrogen, helium) as a working fluid, which makes the operation of the unit dangerous;
• The high-temperature resistance of steel alloys and their thermal conductivity complicates the engine manufacturing process. Significant heat losses in the heat exchanger reduce the efficiency of the unit, and the use of specific materials make the manufacture of the engine expensive;
• To adjust and transition of the engine from the mode to mode, you need to apply special control devices.

Using

Stirling engine found his niche and actively applied where dimensions and omnivores are important criterion:

• Engine stirling electric generator.

The heat transformation mechanism into electrical energy. It is often found products used as portable tourist generators, installations for the use of solar energy.

• Engine, like a pump (electrician).

Engine is used to install in the contour heating systems, saving on electrical energy.

• Engine as a pump (heater).

In countries with a warm climate, the engine is used as a premises heater.

Stirling engine on a submarine:

• Engine as a pump (cooler).

Almost all refrigerators in their design use heat pumps, installing the stirling engine, save resources.

• Engine, as a pump that creates ultra-low degrees of heating.

The device is used as a refrigerator. For this, the process is launched in the opposite direction. The aggregates liquefit gas, cooled measuring elements in accurate mechanisms.

• Engine for underwater technology.

Summer ships of Sweden and Japan work through the engine.

Stirling engine as solar installation:

• Engine as energy battery.

Fuel in such aggregates, salt melts, the engine is used as a source of energy. Motor in power reserves is ahead of chemical elements.

• Solar engine.

Transform the energy of the sun into electricity. Substance in this case, hydrogen or helium. The engine is placed in the focus of the maximum concentration of the energy of the Sun, created using a parabolic antenna.

The main principle of operation of the stirling engine is constantly alternating heating and cooling the working fluid in a closed cylinder. Usually, air acts as a working fluid, but hydrogen and helium are also used.

The cycle of the stirling engine consists of four phases and divided by two transition phases: heating, expansion, transition to cold source, cooling, compression and transition to heat source. Thus, when moving from a warm source to a cold source, there is an expansion and compression of the gas in the cylinder. This changes the pressure, due to which you can get useful work. Since the theoretical explanations of the wing of scientists of husbands, listen to their times tedious, so let's turn to a visual demonstration of the engine of Sterling.

How does the stirling engine
1. The main source of heat heats the gas at the bottom of the heat exchange cylinder. The pressure generated pushes the working piston up.
2. Machine pushes the casual piston down, thereby moving the heated air from the bottom to the cooling chamber.
3. Follows cool and compressing, the working piston lowers down.
4. The extensive piston rises up, thereby moving the cooled air into the lower part. And the cycle is repeated.

In the stirling machine, the working piston movement is shifted by 90 degrees relative to the movement of the piston-displacer. Depending on the sign of this shift, the machine can be an engine or heat pump. When shifting 0 degrees, the machine does not produce any work (except for friction losses) and does not produce it.

Another invention of stirling, which increased engine efficiency, became a regenerator, which is a chamber filled with wire, granules, corrugated foil to improve the heat transfer of the undergoing gas (in the figure, the regenerator is replaced by the ribs of the cooling radiator).

In 1843, James Stirling used this engine at the factory, where he worked as an engineer at that time. In 1938, Philips invested in a stirling engine with a capacity of more than two hundred horsepower and returns more than 30%.

The advantages of the engine Stirling:

1. omnivorous. You can use any fuel, the main thing is to create a temperature difference.
2. Low noise. Since the work is built on pressure drop working fluidand not on arson of the mixture, then noise compared to the internal combustion engine is significantly lower.
3. Easy design, hence the high margin of safety.

However, all these advantages in most cases are crossed by two large disadvantages:

1. Large dimensions. The working fluid needs to be cooled, and this leads to a significant increase in mass and sizes due to increased radiators.
2. Low efficiency. Heat is not supplied to the working fluid directly, but only through the walls of heat exchangers, respectively, the loss of the efficiency of the CPD.

With the development of the internal combustion engine, the stirling engine left ... No not in the past, but in the shadow. It is successfully operated as auxiliary power plants on submarines, in thermal pumps on thermal power plants, as transducers of solar and geothermal energy into electrical, space projects are associated with the creation of power plants operating on radioisotope fuel (radioactive decay occurs with temperature release, Who did not know). Who knows, maybe one day the stirling engine is waiting for a big future!