Prospects for the Russian aviation engine industry. Jet engine operation diagram

Experimental samples of gas turbine engines (GTE) first appeared on the eve of World War II. The developments came to life in the early fifties: gas turbine engines were actively used in military and civil aircraft construction. At the third stage of introduction into industry, small gas turbine engines, represented by microturbine power plants, began to be widely used in all areas of industry.

General information about gas turbine engines

The operating principle is common to all gas turbine engines and consists in transforming the energy of compressed heated air into mechanical work gas turbine shaft. The air entering the guide vane and compressor is compressed and in this form enters the combustion chamber, where fuel is injected and the working mixture is ignited. Gases formed as a result of combustion are under high pressure pass through the turbine and rotate its blades. Part of the rotational energy is spent on rotating the compressor shaft, but most of the energy of the compressed gas is converted into useful mechanical work of rotating the turbine shaft. Among all internal combustion engines (ICE), gas turbine units have the greatest power: up to 6 kW/kg.

Gas turbine engines operate on most types of dispersed fuel, which makes them stand out from other internal combustion engines.

Problems of developing small TGDs

As the size of the gas turbine engine decreases, the efficiency and specific power decrease compared to conventional turbojet engines. At the same time specific value fuel consumption also increases; the aerodynamic characteristics of the flow sections of the turbine and compressor deteriorate, and the efficiency of these elements decreases. In the combustion chamber, as a result of a decrease in air flow, the combustion efficiency of the fuel assembly decreases.

A decrease in the efficiency of gas turbine engine components with a decrease in its dimensions leads to a decrease in the efficiency of the entire unit. Therefore, when modernizing a model, designers pay special attention increasing the efficiency of individual elements, up to 1%.

For comparison: when the compressor efficiency increases from 85% to 86%, the turbine efficiency increases from 80% to 81%, and the overall Engine efficiency increases immediately by 1.7%. This suggests that for a fixed fuel consumption, the specific power will increase by the same amount.

Aviation gas turbine engine "Klimov GTD-350" for the Mi-2 helicopter

The development of the GTD-350 first began in 1959 at OKB-117 under the leadership of designer S.P. Izotov. Initially, the task was to develop a small engine for the MI-2 helicopter.

At the design stage, experimental installations were used, and the node-by-unit finishing method was used. In the process of research, methods for calculating small-sized bladed devices were created, and constructive measures were taken to dampen high-speed rotors. The first samples of a working model of the engine appeared in 1961. Air tests of the Mi-2 helicopter with GTD-350 were first carried out on September 22, 1961. According to the test results, two helicopter engines were torn apart, re-equipping the transmission.

The engine passed state certification in 1963. Serial production opened in the Polish city of Rzeszow in 1964 under the leadership of Soviet specialists and continued until 1990.

Ma l The second domestically produced gas turbine engine GTD-350 has the following performance characteristics:

— weight: 139 kg;
— dimensions: 1385 x 626 x 760 mm;
— rated power on the free turbine shaft: 400 hp (295 kW);
— free turbine rotation speed: 24000;
— operating temperature range -60…+60 ºC;
— specific fuel consumption 0.5 kg/kW hour;
— fuel — kerosene;
— cruising power: 265 hp;
— takeoff power: 400 hp.

For flight safety reasons, the Mi-2 helicopter is equipped with 2 engines. The twin installation allows the aircraft to safely complete the flight in the event of failure of one of the power plants.

GTD - 350 per at the moment is morally obsolete; modern small aircraft require more powerful, reliable and cheaper gas turbine engines. At the present moment, new and promising domestic engine is MD-120, Salyut Corporation. Engine weight - 35 kg, engine thrust 120 kgf.

General scheme

The design of the GTD-350 is somewhat unusual due to the location of the combustion chamber not immediately behind the compressor, as in standard models, but behind the turbine. In this case, the turbine is attached to the compressor. This unusual arrangement of components reduces the length of the engine power shafts, therefore reducing the weight of the unit and allowing for high rotor speeds and efficiency.

During engine operation, air enters through the VHA, passes through the axial compressor stages, the centrifugal stage and reaches the air collecting scroll. From there, through two pipes, air is supplied to the rear of the engine to the combustion chamber, where it reverses the direction of flow and enters the turbine wheels. The main components of the GTD-350 are: compressor, combustion chamber, turbine, gas collector and gearbox. Engine systems are presented: lubrication, control and anti-icing.

The unit is divided into independent units, which makes it possible to produce individual spare parts and ensure their quick repair. The engine is constantly being improved and today its modification and production is carried out by Klimov OJSC. The initial resource of the GTD-350 was only 200 hours, but during the modification process it was gradually increased to 1000 hours. The picture shows the general mechanical connection of all components and assemblies.

Small gas turbine engines: areas of application

Microturbines are used in industry and everyday life as autonomous sources electricity.
— The power of microturbines is 30-1000 kW;
— volume does not exceed 4 cubic meters.

Among the advantages of small gas turbine engines are:
— wide range of loads;
— low vibration and noise level;
- work for various types fuel;
- small dimensions;
— low level of exhaust emissions.

Negative points:
— complexity electronic circuit(in the standard version, the power circuit is performed with double energy conversion);
— a power turbine with a speed maintenance mechanism significantly increases the cost and complicates the production of the entire unit.

To date, turbogenerators have not received such wide distribution in Russia and in post-Soviet space, as in the USA and Europe due to the high cost of production. However, according to calculations, a single autonomous gas turbine unit with a power of 100 kW and an efficiency of 30% can be used to supply energy to standard 80 apartments with gas stoves.

A short video of the use of a turboshaft engine for an electric generator.

By installing absorption refrigerators, a microturbine can be used as an air conditioning system and for simultaneous cooling of a significant number of rooms.

Automotive industry

Small gas turbine engines demonstrated satisfactory results during road tests, however, the cost of the vehicle increases many times due to the complexity of the design elements. Gas turbine engine with a power of 100-1200 hp. have characteristics similar to gasoline engines, however, mass production of such cars is not expected in the near future. To solve these problems, it is necessary to improve and reduce the cost of all components of the engine.

Things are different in the defense industry. The military does not pay attention to cost; performance is more important to them. The military needed a powerful, compact, trouble-free power plant for tanks. And in the mid-60s of the 20th century, Sergei Izotov, the creator of power plant for MI-2 - GTD-350. Izotov Design Bureau began development and eventually created the GTD-1000 for the T-80 tank. Perhaps this is the only positive experience of using gas turbine engines for ground transport. The disadvantages of using an engine on a tank are its gluttony and pickiness about the cleanliness of the air passing through the working path. Below is presented short video operation of the tank GTD-1000.

Small aviation

Today, the high cost and low reliability of piston engines with a power of 50-150 kW do not allow Russian small aviation to confidently spread its wings. Engines such as Rotax are not certified in Russia, and Lycoming engines used in agricultural aviation are obviously overpriced. In addition, they run on gasoline, which is not produced in our country, which further increases the cost of operation.

It is small aviation, like no other industry, that needs small gas turbine engine projects. By developing the infrastructure for the production of small turbines, we can confidently talk about the revival of agricultural aviation. Abroad, a sufficient number of companies are engaged in the production of small gas turbine engines. Scope of application: private aircraft and drones. Among the models for light aircraft are the Czech engines TJ100A, TP100 and TP180, and the American TPR80.

In Russia, since the times of the USSR, small and medium-sized gas turbine engines have been developed mainly for helicopters and light aircraft. Their resource ranged from 4 to 8 thousand hours,

Today, for the needs of the MI-2 helicopter, small gas turbine engines of the Klimov plant continue to be produced, such as: GTD-350, RD-33, TVZ-117VMA, TV-2-117A, VK-2500PS-03 and TV-7-117V.

Experimental setup for direct laser growth based on a high-power fiber laser

Interesting fact: there are only four countries in the world that have a full cycle of production of rocket engines and jet engines for aircraft. Among them is Russia, which is not only competitive in some types of products, but is also a leader. Evil tongues claim that all that Russia has in this area are the remnants of Soviet luxury, and there is nothing of its own.

As you know, talking your tongue is not moving your bags. In fact, Russia today is not lagging behind other countries and is actively developing new methods for manufacturing aircraft engine parts. This is done by the Institute of Laser and Welding Technologies of Peter the Great St. Petersburg Polytechnic University under the leadership of the director of the institute, Doctor of Technical Sciences, Professor Gleb Andreevich Turichin. The project his group is working on is called: “Creating a technology for high-speed manufacturing of aircraft engine parts and components using heterophase powder metallurgy methods.”

If the name of the institute contains the word “laser”, then we can assume that the laser is an important part of this technology. That's how it is. A jet of metal powder and other components is applied to the workpiece, and a laser beam heats the powder, which leads to sintering. And so on several times until you receive the desired product. The process is reminiscent of layer-by-layer growing of parts. The composition of the powder can be changed during production and parts can be obtained with different properties in different parts.

The products obtained in this way have strength at the level of hot rolled steel. Moreover, they do not require additional processing after manufacturing. But this is not the main thing! At existing methods The manufacture of jet engine parts requires several technological operations, which can take up to three thousand hours in the case of complex products. New method allows you to reduce production time by 15 times!

The installation itself in which all this happens, called by the developers a technological machine, is a large metal sealed chamber with a controlled atmosphere. All work is carried out by a robot, whose arm is equipped with replaceable spray heads. This was all invented at the Institute. The Institute has developed a management system for this entire process.

The first stage of the project was completed last year. Then they were developed mathematical models transferring powder particles to the surface of the product and heating them with a laser beam. But this does not mean that the work began from scratch. By that time, the institute’s employees were able to grow a conical funnel with the specified properties on a pilot technological installation, which convinced Kuznetsov OJSC (a division of the United Propulsion Corporation, Samara) to join, financing half of its cost. The Scientific and Technical Council of the Military-Industrial Commission of the Russian Federation also supported the project.

The project is due to be completed by the end of next year, but is already ahead of schedule. One technological machine is already ready and the second one is being installed. Instead of developing technology for manufacturing one part, specialists from St. Petersburg learned how to make twenty! This became possible not only thanks to the hard work and enthusiasm of the project participants, but also thanks to the great interest of the United Engine Corporation to quickly move from experimental work to industrial use of new technology.

Another important part of the work is the redesign of engines and their parts for growing technology. And that's done too. Employees of OJSC Kuznetsov have already compiled all the documentation for the production of a gas turbine generator using this method and are preparing to receive equipment for laser growing of products, training employees to work on this equipment.

We can safely say that the mass introduction of the new method at engine manufacturing enterprises is just around the corner. Of course, other industries interested in such technologies will not stand aside. This is, first of all, the rocket and space industry, as well as enterprises manufacturing power plants for transport, ships and energy. Medical device manufacturers are also interested in this method.

Evgeniy Radugin

OJSC Kuznetsov is a leading engine-building enterprise in Russia. It carries out the design, manufacture and repair of rocket, aircraft and gas turbine installations for gas industry and energy.

These engines were used to launch manned spaceships"Vostok", "Voskhod", "Soyuz" and automatic transport cargo spacecraft "Progress". 100% of manned space launches and up to 80% of commercial ones are carried out using RD107/108 engines and their modifications produced in Samara.

The plant's products have special meaning to maintain combat readiness long-range aviation Russia. At Kuznetsov, engines for the Tu-95MS long-range bombers, for the Tu-22M3 bombers and for the unique Tu-160 were designed, produced and technically maintained.

1. 55 years ago, rocket engines began to be mass-produced in Samara, which were not only launched into orbit, but have been in use for more than half a century Russian cosmonautics and heavy aviation. The Kuznetsov enterprise, which is part of the Rostec State Corporation, united several large Samara factories. At first they were engaged in the production and maintenance of engines for launch vehicles of the Vostok and Voskhod rockets, now - for the Soyuz. The second direction of Kuznetsov’s work today is power plants for aircraft.

OJSC Kuznetsov is part of the United Engine Corporation (UEC).

2. . This is one of the initial stages of the engine manufacturing process. High-precision processing and testing equipment is concentrated here. For example, the DMU-160 FD milling processing center is capable of processing large-sized parts of complex shape with a diameter of up to 1.6 meters and a weight of up to 2 tons.

3. The equipment is operated in 3 shifts.

4. Processing on a rotary lathe.

5. NK-32 is installed on the Tu-160 strategic bomber, and NK-32-1 is installed on the Tu-144LL flying laboratory. The installation speed allows you to process seams up to 100 meters per minute.

6. . This site is capable of casting blanks with a diameter of up to 1,600 mm and a weight of up to 1,500 kg, required for housing parts of gas turbine engines for industrial and aviation applications. The photo shows the process of pouring a part in a vacuum melting furnace.

10. The test involves cooling a bath of alcohol using liquid nitrogen to a specified temperature.

20. Assembling the next one prototype engine NK-361 for Russian railway. A new direction of development of OJSC Kuznetsov is the production of mechanical drives of the GTE-8.3/NK power unit for the traction section of a main gas turbine locomotive based on the NK-361 gas turbine engine.

21. The first prototype of a gas turbine locomotive with an NK-361 engine in 2009, during tests on the experimental ring in Shcherbinka, carried a train weighing more than 15 thousand tons, consisting of 158 cars, thereby setting a world record.

24. - turbojet engine for the Tu-22M3 aircraft, the main Russian bomber medium range. Along with NK-32 for a long time is one of the most powerful aircraft engines in the world.

Gas turbine engine NK-14ST used as part of a gas transportation unit. The interesting thing is that the engine uses natural gas, pumped through pipelines as fuel. It is a modification of the NK-12 engine, which was installed on strategic bomber Tu-95.

29. Final assembly workshop for serial rocket engines. The RD-107A/RD-108A engines developed by NPO Energomash OJSC are assembled here. These propulsion systems are equipped with the first and second stages of all Soyuz-type launch vehicles.

30. The enterprise’s share in the rocket engine segment on the Russian market is 80%, in manned launches - 100%. Engine reliability is 99.8%. Launches of launch vehicles with engines of JSC Kuznetsov are carried out from three cosmodromes - Baikonur (Kazakhstan), Plesetsk (Russia) and Kourou (French Guiana). The launch complex for Soyuz will also be built at the Russian Vostochny Cosmodrome (Amur Region).

33. Here, in the workshop, work is underway on the adaptation and assembly of the NK-33 rocket engine, intended for the first stage of the Soyuz-2-1v light-class launch vehicle.

34. - one of those that was planned to be destroyed after closure lunar program. The engine is easy to operate and maintain, and at the same time has high reliability. Moreover, its cost is two times lower than the cost of existing engines of the same thrust class. NK-33 is in demand even abroad. Such engines are installed on the American Antares rocket.

36. In the final assembly shop of rocket engines there is a whole gallery with photographs of Soviet and Russian cosmonauts who went into space on rockets with Samara engines.

41. at the stand. A few minutes before the start of the fire tests.

There is only one way to confirm the almost one hundred percent reliability of a product: send the finished engine for testing. It is mounted on a special stand and launched. The propulsion system must operate as if it were already launching a spacecraft into orbit.

42. Over more than half a century of work, Kuznetsov produced about 10 thousand liquid rocket engines of eight modifications, which launched more than 1,800 launch vehicles of the Vostok, Voskhod, Molniya and Soyuz types into space.

43. When ready for a minute, water is supplied to the torch cooling system, creating a water carpet that reduces the temperature of the torch and the noise from the running engine.

44. When testing an engine, about 250 parameters are recorded, by which the quality of the engine’s manufacturing is assessed.

47. Preparing the engine at the stand lasts several hours. It is connected with sensors, their functionality is checked, the lines are pressure tested, and the operation of the stand and engine automation is comprehensively checked.

48. Technological control tests last about a minute. During this time, 12 tons of kerosene and about 30 tons of liquid oxygen are burned.

49. The tests are over. After this, the engine is sent to the assembly shop, where it is disassembled, components are inspected, assembled, final inspection is carried out, and then sent to the customer - to JSC RCC Progress. There it is installed on the rocket stage.

In which air is the main component of the working fluid. In this case, the air entering the engine from surrounding atmosphere, is subjected to compression and heating.

Heating is carried out in combustion chambers by burning fuel (kerosene, etc.) using atmospheric oxygen as an oxidizer. In case of use nuclear fuel The air in the engine is heated in special heat exchangers. According to the method of preliminary air compression, WRDs are divided into non-compressor and compressor (gas turbine) ones.

In non-compressor jet engines, compression is carried out only due to the high-speed pressure of the air flow impinging on the engine in flight. In compressor jet engines, air is additionally compressed in a compressor driven by a gas turbine, which is why they are also called turbocompressor or gas turbine engines (GTVRE). In compressor jet engines, heated high-pressure gas, giving up part of its energy to the gas turbine that rotates the compressor, entering the jet nozzle, expands and is ejected from the engine at a speed exceeding the flight speed of the aircraft. This creates the traction force. Such WRDs are classified as direct reaction engines. If part of the energy of the heated gas given to the gas turbine becomes significant and the turbine rotates not only the compressor, but also a special propulsion device (for example, an air propeller), which also ensures the creation of the main thrust force, then such VRE are called indirect engines. reactions.

Usage air environment as a component of the working fluid allows you to have only one fuel on board the aircraft, the share of which in the volume of the working fluid in the VRD does not exceed 2-6%. The wing lift effect allows flight with engine thrust that is significantly lower than the weight of the aircraft. Both of these circumstances predetermined the predominant use of WFD on aircraft during flights in the atmosphere. Compressor gas turbine jet engines, which are the main type of engines in modern military and civil aviation, are especially widespread.

At high supersonic flight speeds (M > 2.5), the increase in pressure only due to dynamic air compression becomes quite large. This makes it possible to create compressor-free VREs, which, based on the type of working process, are divided into direct-flow (ramjet) and pulsating (PuRjet). The ramjet consists of an input device (air intake), a combustion chamber and an output device (jet nozzle). In supersonic flight, the oncoming air flow is slowed down in the air intake channels, and its pressure increases. Compressed air enters the combustion chamber, where fuel (kerosene) is injected through the nozzle. The combustion of the kerosene-air mixture in the chamber (after its preliminary ignition) occurs at practically a slightly varying pressure. High-pressure gas heated to a high temperature (more than 2000 K) is accelerated in the jet nozzle and flows out of the engine at a speed exceeding the flight speed of the aircraft. Ramjet parameters largely depend on altitude and flight speed.

At flight speeds less than double the speed of sound (M > 5.0-6.0), ensuring high ramjet efficiency is associated with difficulties in organizing the combustion process in a supersonic flow and other features of high-speed flows. Ramjet engines are used as supersonic propulsion engines cruise missiles, engines of the second stages of anti-aircraft guided missiles, flying targets, jet propeller engines, etc.

The jet nozzle also has variable dimensions and shape. A ramjet-powered aircraft usually takes off using rocket power units (liquid or solid fuel). The advantages of ramjet engines are the ability to operate effectively at high speeds and flight altitudes than compressor WFDs; higher efficiency compared to liquid ones rocket engines(since ramjet engines use atmospheric oxygen, and oxygen is introduced into liquid rocket engines as a fuel component), simplicity of design, etc.

Their disadvantages include the need to pre-accelerate the JIA with other types of engines and low efficiency at low flight speeds.

Depending on the speed, ramjet engines are divided into supersonic (SPVRJET) with M from 1.0 to 5.0 and hypersonic (Scramjet) with M > 5.0. Scramjet engines are promising for aerospace vehicles. Pu-jet engines differ from ramjet engines by the presence of special valves at the entrance to the combustion chamber and the pulsating combustion process. Fuel and air enter the combustion chamber periodically when the valves are open. After combustion of the mixture, the pressure in the combustion chamber increases and the inlet valves close. High pressure gases with high speed rush into a special exit device and are thrown out of the engine. Towards the end of their expiration, the pressure in the combustion chamber decreases significantly, the valves open again, and the work cycle repeats. PURD engines have found limited use as propulsion engines for subsonic cruise missiles, in aircraft models, etc.

In front jet engine the fan is located. He takes the air out external environment, sucking it into the turbine. In rocket engines, air replaces liquid oxygen. The fan is equipped with multiple titanium blades with special form.

They try to make the fan area large enough. In addition to air intake, this part of the system also participates in cooling the engine, protecting its chambers from destruction. Behind the fan is a compressor. It forces air into the combustion chamber under high pressure.

One of the main structural elements of a jet engine is the combustion chamber. In it, fuel is mixed with air and ignited. The mixture ignites, accompanied by strong heating of the housing parts. The fuel mixture expands under high temperature. In fact, a controlled explosion occurs in the engine.

From the combustion chamber, a mixture of fuel and air enters the turbine, which consists of many blades. The jet stream puts pressure on them and causes the turbine to rotate. The force is transmitted to the shaft, compressor and fan. A closed system is formed, the operation of which only requires a constant supply of the fuel mixture.

The last part of a jet engine is the nozzle. A heated flow enters here from the turbine, forming a jet stream. This part of the engine is also supplied with cold air from the fan. It serves to cool the entire structure. The air flow protects the nozzle cuff from the harmful effects of the jet stream, preventing parts from melting.

How does a jet engine work?

The working fluid of the engine is a jet. It flows out of the nozzle at a very high speed. This generates a reactive force that pushes the entire device into opposite direction. The traction force is created solely by the action of the jet, without any support from other bodies. This feature of the jet engine allows it to be used as a power plant for rockets, aircraft and spacecraft.

In part, the operation of a jet engine is comparable to the action of a stream of water flowing from a hose. Under enormous pressure, the liquid is supplied through the hose to the narrowed end of the hose. The speed of water leaving the nozzle is higher than inside the hose. This creates a back pressure force that allows the firefighter to hold the hose only with great difficulty.

The production of jet engines is a special branch of technology. Since the temperature of the working fluid here reaches several thousand degrees, engine parts are made of high-strength metals and materials that are resistant to melting. Individual parts of jet engines are made, for example, from special ceramic compounds.

Video on the topic

The function of heat engines is to convert thermal energy into useful mechanical work. The working fluid in such installations is gas. It presses forcefully on the turbine blades or on the piston, causing them to move. The most simple examples Heat engines are steam engines, as well as carburetor and diesel internal combustion engines.

Instructions

Piston heat engines They consist of one or more cylinders, inside of which there is a piston. Hot gas expands in the volume of the cylinder. In this case, the piston moves under the influence of gas and performs mechanical work. Such a heat engine converts the reciprocating motion of the piston system into shaft rotation. For this purpose, the engine is equipped with a crank mechanism.

External combustion heat engines include steam engines in which the working fluid is heated when fuel is burned outside the engine. Heated gas or steam under high pressure and high temperature fed into the cylinder. At the same time, the piston moves, and the gas gradually cools, after which the pressure in the system becomes almost equal to atmospheric pressure.

The exhaust gas is removed from the cylinder, into which the next portion is immediately supplied. To return the piston to its initial position, flywheels are used, which are attached to the crank shaft. Such heat engines can provide single or double action. In double-acting engines, there are two stages of piston stroke per shaft revolution; in single-acting engines, the piston makes one stroke in the same time.

The difference between internal combustion engines and the systems described above is that the hot gas here is obtained by burning the fuel-air mixture directly in the cylinder, and not outside it. Supplying the next portion of fuel and