Gas Turbine Engine Operation

All jet engines break down to three basic types: gas turbine engines, ram jets, and rockets. Gas turbine engines are widely used in civil aviation. Gas turbine engines are classified into turbojets, turboprops, turboshafts and turbofans. A gas turbine engine consists of the following main components: an air inlet, a compressor, a burner or a combustion chamber, a turbine, and an exhaust nozzle. An air inlet provides air for a compressor which compresses the air and passes it to a combus­tion chamber. There the air is mixed with fuel and ignited, combustion takes place, and the heated gases enter a turbine. The energy of heated gases is taken by a turbine. This energy is used to drive the shaft of an engine. The exhaust gases leave an engine through an exhaust nozzle and provide thrust.

Exercise 20. Answer the following questions.

1. What are three basic types of jet engines?

2. What type of a jet engine is of wide use in civil aviation?

3. What are the main components of a gas turbine engine?

4. What component of the jet engine provides air for the com­pressor?

5. What does a compressor do?

6. Where does combustion take place?

7. In what form is the energy of heated gases transferred to the turbine?

8. What purpose is the extracted power used for?

9. What component of the jet engine do the heated gases leave the engine through?

10. What do the exhaust gases provide?

Exercise 21. Find in the text English equivalents to the following words:

У вигляді швидкості, газотурбінний двигун, тяга, вихлопні гази, класифікуются як, нагріті гази, енергія нагрітих газів, приводити в рух, вал двигуна, крізь вихлопне сопло, широко використовуються, відбувається (має місце), турбовальний двигун, турбо-вентиляційний.

Exercise 22. Put in the missing words.

(velocity, exhaust, component, thrust, takes place,

heated, extracts, shaft, nozzle, to drive)

1. A combustion chamber is one of the main ___of a gas turbine engine.

2. A very important process ___________ in a burner.

3. The turbine _____________ power from ____________ gases.

4. A compressor and a turbine are on the same ____________.

5. The energy of heated gases has the form of _______________.

6. This energy is used ___________ the compressor.

7. _____gases passing through the exhaust _______ create ________.

Exercise 23. Substitute the underlined words by their synonyms.

Translate the sentences.

(piston, combustion chamber, speed, heated, supplies,

leave, are widely used, break down)

1. All jet engines may be classified as gas turbine engines, ram jets and rockets.

2. Gas turbine engines are of wide use in civil aviation.

3. Air inlet provides air for a compressor.

4. Reciprocating engines use high octane fuels.

5. Combustion takes place in a burner.

6. High temperature gases enter a turbine.

7. They pass through the engine at great velocity.

Exercise 24. Put general questions to the sentences. Give short answers.

1. Jet engines completely replaced piston engines.

2. The early jet engines had the speed of about 960 km/hr.

3. Jet engines provided power necessary for overcoming sound barrier.

4. The Ukrainian jet engine designers made a great contribution to the development of civil aviation.

5. Earlier jet engines operated only at subsonic speeds.

Exercise 25. Put questions to the underlined words.

1. Combustion takes place in a burner.

2. Air inlets supply air for compressor.

3. Exhaust gases provide thrust.

4. A turbine drives a compressor.

5. Velocity transforms into useful work in a turbine.

6. The exhaust gases leave the engine through the exhaust nozzle.

7. Compression of the air takes place in a compressor.

8. The compressed air is mixed with fuel and ignited.

9. The temperature of the combustion products is very high.

Exercise 26. The following sentences are wrong. Correct them by transforming the sentences into negative form. Translate them.

1. Early jet engines flew at supersonic speeds.

2. The speed of piston-engined airplanes exceeded 700 km/hr.

3. The first in the history of aviation aircraft powered by a steam engine was a success.

4. Piston engines could develop necessary power to overcome sound barrier.

5. The early aircraft used gasoline as fuel.

Exercise 27. Put all types of questions to the sentences.

1. The first jet engines appeared before the World War II.

2. The possibility of rockets were practically limitless.

3. Piston engined airplanes developed speed of 500 km/hr.

4. Introduction of jet engines opened a new era in aviation.

5. Piston engines found wide practical application in aviation.

Exercise 28. Translate the text in the written form.