The gas turbine engine is successfully used in tanks and aviation. Unfortunately, a number of design limitations do not allow the use of this progressive design as a power plant for a passenger car. The advantage of this type of engines is that they have the highest power density among existing power plants related to engines internal combustion, up to 6 kW/kg. In addition, a gas turbine engine can run on various types liquid fuels, not just gasoline or diesel.

Course: "Gas Turbines: Operation, Operation and Maintenance"

Engineers, technicians, and operations and maintenance personnel who are responsible for the operation, inspection, operation, and Maintenance gas turbines. Consulting companies or any other participant who wants to get acquainted with this equipment.

Analysis of real cases. Debate between participants. Recognize the types of turbines on the market. Understand thermodynamic cycles. Define the intake, compressor, combustion, turbine and exhaust system. Understand the operation, operation and maintenance of gas turbines. Understand auxiliary systems, basic principles of control and protection. Install improvements in your workspace and take action to ensure proper operation and maintenance.

The history of the creation of a gas turbine engine

The first gas turbine was developed in 1519. It differed significantly from modern devices and was used in the "field of small-scale mechanization." The turbine rotated a skewer designed for frying meat. A gas turbine was also used to drive the carts of the inventor John Barber.

One of the first gas turbine engines for tanks was developed by BMW in 1944. It was tested on a self-propelled unit "Panther"

The results were over 300 participants who rated it in polls as an average between "Very Good" and "Excellent". Perm received excellent comments from participants such as: "Very clear, with a lot of experience, very good ability to answer questions"; "Very good distribution of all the topics that were given, a very comprehensive course"; "Highly good stuff in CD and printed book", "Good balance between theory and practice", "I really liked the experiences and operational details shared by the lecturers, which are not in the bibliography".

In 1950, a gas turbine engine was developed for automobiles. The result was an experimental model of the racing car "JET1". The engine of the car was located behind the seats, air intakes were mounted on the sides, and on the upper rear there were holes for the exhaust gases to escape. The rotation speed of the turbine reached 50 thousand revolutions per minute. Gasoline, paraffin oil and diesel fuel were used as fuel. The maximum speed at which the car could move was 140 km / h. Due to the significant fuel consumption, cars with a gas turbine engine were not in great demand.

Energy market trends Technological trends Gas turbine selection variables. Basic combustion turbine Definition of basic concepts Simple variations of the gas turbine cycle Combined cycle cycle. Mufflers for air filtration systems.

Compressor box Compressor diaphragms Pump pumps for mobile compressors and safety valves. Baskets Harvesters Combined fuel transfer lines Fuel injectors Spark plugs Flame detectors. Turbine cylinder and support assembly. Turbine wheels Turbine rotor and turbine compressor cooling system.

The only case of the use of a gas turbine engine in the design of a motorcycle is the MTT Y2K Turbine Superbike with a Rolls-Royce-Allison Model 250 ICE

Having upgraded the device and designed the BRM model, Rover took part in the racing competition in 1963 and set a record: the car accelerated to a speed of 229 km / h. Later, other automobile manufacturers also participated in similar competitions. For example, Howmet produced the TX, which was powered by a gas turbine engine and became a racing favorite on numerous occasions. common use, was produced. Fifty copies of the car called Chrysler Turbine were hand-assembled by the specialists of the Italian coachbuilder Ghia. The cars did not go on sale, but were distributed to volunteers for two years for testing. The experiment was successful, but the launch of a new production required the construction of a plant for the production of new types of engines, and the Chrysler concern did not dare to invest a lot of money. In the seventies, when environmental standards were significantly tightened in the United States, and, in addition, the fuel crisis began, which inflated oil prices, the company refused to continue development.

Introduction The function of the components. Slow start and rotation system Control system and safety valves. Air system: cooling, instrumentation and printing. Lubrication system Fuel system: gas, liquid and engine. Bearings and seals of the fire extinguishing system.

Control system of gas turbines. Distributed Protection System System Operation and maintenance of gas turbines. Principle of operation Constitution of generators Cooling of generators Excitation systems Operation of generators. Additional Information about the course "Turbinas gas".

The device and principle of operation of a gas turbine engine

Once in the compressor, the air is compressed and heated. Then it enters the combustion chamber, where part of the fuel is also supplied. Due to the high speed, air and fuel ignite on impact. During the combustion of the mixture, energy is released, which is converted into mechanical work due to rotation. Part of this energy is used to compress the air in the compressor. The other part goes to the electric generator. After that, the exhaust gases are sent to the utilizer.

Advantages and disadvantages of gas turbine engines

Gas turbine engines are superior to piston engines in many ways. Due to the ability to develop high speeds, the device is characterized by high power, but at the same time it has a compact size. Kerosene or diesel fuel is used as fuel. The mass of a gas turbine engine is 10 times less than the mass of an internal combustion engine of similar power. Due to the absence of rubbing parts, the gas turbine does not require the presence of.

Chrysler engineers, who created the only small-scale gas turbine engine car, found out by experience that the best fuel for gas turbine engines is ordinary kerosene.

The invention of the gas turbine and the development of its original design were made for aircraft research and research jet engines. Later, the use of gas turbines to drive compressors, pumps and generators was adapted. Due to its compact design, light weight and high power compared to traditional internal combustion engines have been widely adopted for industrial applications.

Recently, low power gas turbines have been introduced for industrial applications. In this environment, these turbines are commonly referred to as gas generators. Its purpose is to generate a large volume of high energy gases flowing through the turbine wheel by converting this energy into shaft energy.

The main disadvantage is the increased fuel consumption caused by the need to artificially limit the temperature of the gases. This limitation is due to the fact that in the case of a car, the engine is installed inside the body, and not under the wing, as in an aircraft, for example. Accordingly, the engine temperature should not exceed 700 degrees. Metals resistant to such temperatures are very high cost. This problem is often of interest to scientists, and gas turbine engines with good efficiency indicators should appear in the near future. Obviously, this will happen only if the problem of removing a large amount of heat is solved, which will make it possible to install "non-strangled" engines on cars, in the design of which the problem of efficiency is solved. Among the shortcomings, it should also be noted high quality requirements. atmospheric air and lack of engine braking capability.

The gas turbine is heat engine, which uses air as the motive fluid to provide power. To do this, the air passing through the turbine must be accelerated; this means that the speed or kinetic energy air increase. To get this increase, the pressure is first increased and then heat is added. Finally, the generated energy is converted into power along the axis of the turbine.

Compression - Air is admitted and compressed in the compressor, where the pressure energies and fluid temperature increase. Combustion - Compressed air enters the combustion chambers where high-pressure fuel is injected and burned at approximately constant pressure. Subsequently, the combustion itself is supported.

Two-shaft gas turbine engine equipped with a heat exchanger

This type of engine is the most common. Compared to single-shaft counterparts, these devices meet higher requirements for vehicle dynamics. Two-shaft units assume the presence of a special (to drive the compressor) and traction (to drive the wheels) turbines, the shafts of which are not connected. Such engines improve the dynamic properties of the machine and make it possible to reduce the number of steps in the gearbox.

After abandoning the mass production of cars with gas turbine engines, Chrysler destroyed most of the test specimens so that "the turbines did not get into auto-dismantling"

Extension. The gases of high temperature and pressure expand at high speed through the stages of a gas generating turbine, which converts some of the energy of the potential gases into a shaft to drive an air compressor. Exhaust - In a jet aircraft, the remaining gases from expansion in a turbine are passed through a nozzle to increase its speed and therefore thrust. In industrial applications, the gases are sent to a reaction or power turbine, where the waste energy of the generated gas energy is converted into shaft power to drive a component such as a gas compressor, electrical generator, or pump.

Unlike reciprocating engines, twin-shaft gas turbines assume automatic operation when the load increases. As a result, gear changes are required much later or not at all. With equal power, cars with a two-shaft gas turbine engine accelerate faster than cars with piston engines. The disadvantages of this type are the complexity of manufacturing, an increase in size and weight due to the presence of additional parts: a heat exchanger, gas and air ducts.

Finally, the gases enter the exhaust duct, where their remaining energy can still be used in the heat recovery system. In a turbine, combustion occurs at a constant pressure, while in a conventional engine, combustion occurs at a constant volume.

Figure 5 - Comparison of cycles. In both cycles there are stages of intake, compression, combustion and exhaustion. In a conventional cycle engine, these steps occur in the same place in different time, which is a periodic cycle. Air is allowed from point 1 to point 2, increasing the volume without changing the pressure. From point 2 - 3, the upward movement of the piston results in a decrease in volume, an increase in pressure, and a subsequent increase in temperature, since this is a polytropic compression process. At point 3, ignition occurs with a large increase in the temperature of the mixture.

Gas turbine engine with free-piston gas generator

On the this moment gas turbine engines of this design are the most promising for the construction of automobiles. The device is a unit that combines a reciprocating compressor and a two-stroke diesel engine. In the middle part there is a straight-through blowing cylinder, inside of which there are two pistons interconnected by a special mechanism. When the pistons converge, air is compressed and the fuel ignites. Burnt fuel contributes to the formation of gases, which, when high temperature and pressure provoke a divergence of the pistons to the sides. Further, through the exhaust windows, the gases enter the gas collector. Thanks to the presence of scavenging ports, compressed air enters the cylinder, which assists and prepares the engine for the next cycle. After that, the process is repeated.

A gas turbine engine is a thermal power unit that operates on the principle of reorganizing thermal energy into mechanical energy.

The term "constant volume" is due to the fact that from point 3 to point 4, when the mixture is burned, there is no significant change in volume, but there is a significant increase in pressure. From point 4 to point 5, the expansion occurs with a decrease in temperature and pressure and an increase in volume.

It is important to note that this is the only step where energy can be extracted. When the exhaust valve opens, point 5 to point 2, this results in a rapid pressure drop at constant volume. The piston then rises, forcing the remaining gases to be exhausted.

Turbines operate on the Brayton cycle, which is commonly referred to as the open cycle. Air is admitted and compressed from point 1 to point 2 with a subsequent increase in pressure and temperature and a decrease in volume. From points 2 - 3, we have shown combustion at constant pressure, but with a noticeable increase in volume. This increase in volume is manifested in an increase in the gas flow rate, since there is no noticeable change in the area of ​​this section of the turbine.

Below we will consider in detail how a gas turbine engine works, as well as its device, varieties, advantages and disadvantages.

Distinctive features of gas turbine engines

Today, this type of motor is most widely used in aviation. Alas, due to the peculiarities of the device, they cannot be used for ordinary cars.

From combustion, gases expand in the turbine wheels, which leads to a decrease in pressure and temperature and an increase in volume. The gas turbine consists of. The compressor is a component of a gas turbine where working fluid is under pressure, the dynamic type is always used. In practice, very high compression ratios are usually obtained with two or three axial rotors operating in series, or a rotor with several axial stages followed by a final centrifugal stage.

The air compressor is the turbine component responsible for increasing the air pressure in the Brayton cycle and is driven by the gas generator turbine. An axial compressor is used in these cases because it is specified for higher flow rates than centrifugal in relation to size.

Compared to other internal combustion units, a gas turbine engine has the highest power density, which is its main advantage. In addition, such an engine is able to operate not only on gasoline, but also on many other types of liquid fuel. As a rule, it runs on kerosene or diesel fuel.

Its principle of operation is to accelerate air and then convert it into pressure. It consists of a fixed section where rings with stator ribs are installed and a rotating section consisting of a set of rotors with blades. Each compression stage consists of a rotor with blades and a ring with stator ribs. A rotor with a blade is responsible for the acceleration of air, for example, from a fan. It is at this stage that the air gets work to increase the energy of pressure, velocity and temperature. The ring of stator fins is designed to direct impact air at a favorable angle onto the next stage rotor blades and to assist in slowing down the airflow so that the energy is converted from speed to pressure.

gas turbine and piston engine, which are installed on "passenger cars" by burning fuel, change the chemical energy of the fuel into heat, and then into mechanical energy.

But the process itself is slightly different for these units. In both engines, the intake is first carried out (that is, the air flow enters the engine), then compression and fuel injection occur, after which the fuel assembly ignites, as a result of which it expands greatly and, as a result, is released into the atmosphere.

These machines are designed so that the inlet speed of each rotor is the same for maximum efficiency. This process is repeated in successive stages of the compressor, where each stage contributes a small increase in pressure.

The airflow in the compressor is axis-parallel on a helical path, and the through section decreases from inlet to discharge to maintain a constant air velocity across the operating range as pressure increases with each stage and thus specific gravity. Pressure changes and speed changes at each stage can be seen in the following figures.

The difference lies in the fact that in gas turbine devices all this takes place at the same time, but in different parts of the unit. In the piston, everything is carried out at one point, but in sequence.

Passing through the turbine motor, the air is highly compressed in volume and due to this, the pressure increases by almost forty times.


The last stage stator flaps act as outlet valves that direct the air in a stabilized axial flow to the compressor rear frame and combustion section. The compressor is designed to operate with high efficiency at high speeds. To keep the air flow stable at low speed, a set of movable blades is installed in the air intake, which automatically changes the angle of attack of the blades on the first rotor. Efficiency gradually increases as rotation increases.

To prevent splashes at low speeds, air purification valves are installed. Overvoltage protection is provided by the safety valves installed in the last stages, which are opened by the release of the atmosphere during the acceleration and shutdown phase of the compressor.

The only movement in the turbine is rotational, when, as in other internal combustion units, in addition to the rotation of the crankshaft, the piston also moves.

The efficiency and power of a gas turbine engine is higher than that of a piston engine, despite the fact that the weight and dimensions are smaller.

For economical fuel consumption, the gas turbine is equipped with a heat exchanger - a ceramic disc, which operates from an engine with a low speed.

Combustion in a gas turbine is a continuous process carried out at constant pressure. A constant supply of fuel and air is mixed and burned as it flows through the flame zone. The continuous flame does not touch the walls of the crankcase of the combustion chamber, is stabilized and formed by the distribution of the allowable air flow, which also cools the entire combustion chamber. Mixtures with a wide range of fuel-to-air ratios can be burned because the fuel-air ratio is maintained in the flame zone and excess air is introduced below the flame.

The device and principle of operation of the unit

By design, the engine is not very complex, it is represented by a combustion chamber, where nozzles and spark plugs are equipped, which are necessary for supplying fuel and producing a spark charge. The compressor is equipped on the shaft along with a wheel with special blades.

In addition, the motor consists of such components as a gearbox, an inlet channel, a heat exchanger, a needle, a diffuser and an exhaust pipe.

During the rotation of the compressor shaft, the air flow entering through the intake channel is captured by its blades. After increasing the speed of the compressor to five hundred meters per second, it is forced into the diffuser. The velocity of the air at the outlet of the diffuser decreases, but the pressure increases. Then the air flow is in the heat exchanger, where it is heated by the exhaust gases, and after that the air is supplied to the combustion chamber.

Together with it, fuel gets there, which is sprayed through nozzles. After the fuel is mixed with air, a fuel-air mixture is created, which ignites due to the spark received from the spark plug. At the same time, the pressure in the chamber begins to increase, and the turbine wheel is driven by gases falling on the wheel blades.


As a result, the torque of the wheel is transferred to the transmission of the car, and the exhaust gases are released into the atmosphere.

Engine pros and cons

A gas turbine, like a steam turbine, develops high speed, which allows it to gain good power, despite its compact size.

The turbine is cooled very simply and efficiently, it does not require any additional devices. It has no rubbing elements, and there are very few bearings, due to which the engine is able to function reliably and for a long time without breakdowns.

The main disadvantage of such units is that the cost of the materials from which they are made is quite high. The cost of repairing gas turbine engines is also considerable. But, despite this, they are constantly being improved and developed in many countries of the world, including ours.

The gas turbine is not installed on cars, primarily because of the constant need to limit the temperature of the gases that enter the turbine blades. As a result, the efficiency of the device decreases and fuel consumption increases.

Today, some methods have already been invented that allow increasing the efficiency of turbine engines, for example, by cooling the blades or using the heat of the exhaust gases to heat the air flow that enters the chamber. Therefore, it is quite possible that after a while, developers will be able to create an economical do-it-yourself engine for a car.


Among the main advantages of the unit can also be identified:

  • Low content of harmful substances in exhaust gases;
  • Easy to maintain (no need to change the oil, and all parts are wear-resistant and durable);
  • There are no vibrations, since it is possible to easily balance the rotating elements;
  • Low noise level during operation;
  • Good torque curve characteristic;
  • Start quickly and without difficulty, and the engine response to gas is not late;
  • Increased specific power.

Types of gas turbine engines

According to their structure, these units are divided into four types. The first of these is a turbojet, most of which is installed on high-speed military aircraft. The principle of operation is that the gases leaving the high speed from the engine, push the plane forward through the nozzle.

Another type is turbine propeller. Its device differs from the first one in that it has one more section of the turbine. This turbine is made up of a series of blades that take the rest of the energy from the gases that have passed through the compressor turbine and due to this they rotate the propeller.

The screw can be located both at the rear of the unit and at the front. Exhaust gases are discharged through the exhaust pipes. Such a jet is equipped on aircraft flying at low speed and at low altitude.


The third type is turbofan, which is similar in design to the previous engine, but its 2nd turbine section does not completely take energy from gases and therefore such engines also have exhaust pipes.

The main feature of such an engine is that its fan, closed in a casing, is powered by a turbine. low pressure. Therefore, the engine is also called a 2-circuit engine, since the air flow passes through the unit, which is an internal circuit and through its external circuit, which is only necessary to direct the air flow that pushes the motor forward.

The latest aircraft are equipped with turbofan engines. They operate efficiently at high altitudes and are also economical.

The last type is turboshaft. The scheme and arrangement of a gas turbine engine of this type is almost the same as that of the previous engine, but almost everything is driven from its shaft, which is connected to the turbine. Most often it is installed in helicopters, and even on modern tanks.

Twin piston and small size engine

The most common engine with two shafts, equipped with a heat exchanger. Compared to units that have only 1 shaft, such devices are more efficient and powerful. The 2-shaft engine is equipped with turbines, one of which is designed to drive the compressor, and the other to drive the axles.


Such a unit provides the machine with good dynamic characteristics and reduces the number of speeds in the transmission.

There are also small-sized gas turbine engines. They consist of a compressor, a gas-air heat exchanger, a combustion chamber and two turbines, one of which is located in the same housing with a gas collector.

Small-sized gas turbine engines are mainly used in aircraft and helicopters that cover long distances, as well as in unmanned aerial vehicles and APUs.

Unit with free piston generator

To date, devices of this type are the most promising for cars. The engine device is represented by a block that connects a piston compressor and a 2-stroke diesel engine. In the middle is a cylinder with two pistons connected to each other using a special tool.

The operation of the engine begins with the fact that the air is compressed during the convergence of the pistons and the fuel ignites. Gases are formed due to the burnt mixture, they contribute to the divergence of the pistons at elevated temperatures. Then the gases are in the gas collector. Due to the purge slots, compressed air enters the cylinder, which helps to clean the unit from exhaust gases. Then the cycle starts anew.