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Задание 1. Определите функцию инфинитива и переведите предложения:
1. To land the airplane at night is rather difficult.
2. Our task is to determine the shape of the fuel tank.
3. To find the answer to these questions a number of research rockets were sent into space.
4. There are a number of problems still to be considered.
5. The Russian scientist K.E.Tsiolkovsky was the first to understand the use of rockets in space travel.
Задание 2. Укажите номера предложений, которые переводятся, начиная со слов: «Говорят, что...», «Известно, что...».
1. Wood is said to be one of the oldest materials.
2. He said that the principle of jet propulsion is based on the reaction principle.
3. My chief is said to have finished his experiment last week.
4. The engineer said he had finished the experiment.
5. We know this machine very well.
UNIT 7
Турбовентиляторный двигатель
(двухконтурный турбореактивный двигатель)
Задание 1. Прослушайте, повторите и запомните следующие слова?
fan - вентилятор
turbofan - турбовентиляторный двигатель
feature - особенность, признак,
характерная черта
performance - летные данные (качества,
характеристики
to comprise - включать, заключать в себе,
состоять из …
duct - канал, труба, трубопровод
bypass duct - воздухопровод второго контура
to convert - превращать, преобразовывать
to split (split, split) - разделять, раскалывать
portion - часть
remainder - остальная часть
ratio - отношение, соотношение
bypass ratio - коэффициент двухконтурности
to define - определять
to add - увеличивать, добавлять
additional (thrust, energy) - добавочные, дополнительный
to derive - получать, производить
to locate - располагать
to be located - располагаться
to install - устанавливать
installation - установка
Задание 2. Подберите синонимы:
1. performance 1. to be situated
2. to comprise 2. to increase
3. to convert 3. characteristics
4. to split 4. relation
5. portion 5. to consist of
6. to be located 6. to transform
7. ratio 7. part
8. to add 8. to separate
Задание 3. Подберите антонимы:
1. to enter 1. high
2. low 2. to stop
3. down-stream 3. uneconomic
4. to continue 4. to leave
5. efficient 5. heavier
6. to expand 6. inefficient
7. lighter 7. to compress
8. economic(al) 8. up-stream
Задание 4. Прочтите и переведите следующие предложения.
The turbofan engine combines features of both the turbojet and turboprop engines.
A gas turbine comprises 3 main sections: the compressor section, the combustion section and the turbine section.
The size of the combustion chamber often defines the maximum diameter of the engine.
The function of a diffuser is to convert kinetic energy of the entering air into a pressure rise.
The combustion chamber is located on the outside of the engine behind the compressor.
In turbofan engines the entering air flow is split into two portions: one portion enters the bypass duct and the remainder flows through the compressor, combustion chamber and turbine.
In a turboprop engine a portion of the potential energy is derived by additional turbine engines.
The bypass ratio is the ratio of the air flow through the bypass duct to the air flow through the gas generator.
The turbofan engine has performance characteristics somewhere between the turbojet and turboprop engines.
The turbofan engines can practically be used for most types of airplane installations.
Задание 5. Прочтите предложения, вставляя пропущенные слова. Предложения переведите.
In the turbofan engine the fan may be ….. behind the gas generator turbine.
The exhaust gases are expanded in the ….. to a velocity greater than the …..
The function of the diffuser is ….. the kinetic energy of the entering air into a static ….. rise.
The ….. provides the power for both the fan and the compressor.
The propulsive thrust of the engines is derived from the high velocity exhaust of both the ….. and the gas generator.
fan, turbine, located, pressure, exhaust nozzle, flight velocity.
Задание 6. Переведите следующие словосочетания:
airplane installations; propulsive thrust; transport type aircraft; high velocity exhaust; gas generator turbine; compared with the turboprop; bypass ratio; performance characteristics.
Задание 7. Прочтите и переведите следующие слова:
transport; generator; diffuser; front; compressor; turbine; function; to convert, kinetic energy; static; portion; to locate; efficient; economical.
Задание 8. Прослушайте, прочтите и переведите текст.
Turbofan Engines
The turbofan engine combines features of both the turbojet and turboprop engines. It has performance characteristics somewhere between the other two engines.
The engine comprises a diffuser, a fan, a mechanical duct, and an exhaust nozzle. The function of the diffuser is to convert the kinetic energy of the entering air into a static pressure rise. The diffuser delivers its air to a fan which further compresses it. Then the air flow is split and a portion enters the bypass duct, while the remainder continues into the mechanical compressor, combustion chamber and turbine. The ratio of the airflow through the bypass duct to the air flow through the gas generator is defined as the bypass ratio. The turbine provides the power for both the fan and the compressor. However, there is still considerable energy in the gases down-stream of the turbine. The exhaust gases are therefore further expanded in the exhaust nozzle to a velocity greater than the flight velocity, producing thrust for propulsion. The bypass air is also expanded to a velocity higher than the flight velocity, producing additional thrust for propulsion. Thus the turbofan engine derives its propulsive thrust from the high velocity exhausts of both the bypass air and the gas generator gases.
The turbofan engine is somewhat more efficient than the turbojet at low speeds. Compared with the turboprop it is lighter, less economical at low speeds and more economical at high speeds. The turbofan engines are practically used for most types of airplane installations, especially for transport type aircraft.
Задание 9. Согласитесь илиопровергните утверждения. Начинайте предложения с фраз: I’m afraid that’s wrong. You are quite right/ You are wrong. That’s not quite so. I think you are mistaken. As far as I know. I think so/ I don’t think so/ According to the text.
The turbofan engine has performance characteristics somewhere between air-breathing engines and rocket engines.
The function of the diffuser is to provide power for the mechanical compressor.
The ratio of the air flow through the bypass duct to the air flow through the gas generator is defined as the pressure ratio.
The diffuser delivers its air to a fan, which further compresses it.
The turbofan engine is somewhere more efficient that the turbojet at low speeds.
Compared with the turboprop it is heavier, more economical at low speeds and less economical at high speeds.
Задание 10. Прочтите и переведите предложения.
In the turbofan engine the fan mat be located either in front of the gas turbine or behind it.
The first generation of turbofan designs had a bypass ratio of approximately 1:1, that is, about 50 per cent of the air went through the engine as primary airflow and about 50 per cent went through the fan as secondary airflow.
The efficiency of the fan engine is increased over that of the jet by converting more of the fuel energy into pressure energy rather than the kinetic energy of a high-velocity exhaust gas stream.
Fan engines show definite advantages over the jet engines at speed below Mach 1, the speed of present-day commercial aircraft.
Задание 11. Переведите вопросы на английский язык и ответьте на них.
Какие характерные черты объединяет турбовентиляторный двигатель?
Каковы его главные компоненты?
Куда диффузор подает входящий (поступающий) воздух?
Как разделяется воздушный поток в турбовентиляторном двигателе?
Создает ли турбина мощность и для вентилятора и для компрессора?
Где дальше расширяются выхлопные газы, создавая, таким образом, тягу для движения вперед?
Откуда турбовентиляторный двигатель извлекает эффективную тягу (propulsive thrust)?
Является ли турбовентиляторный двигатель более эффективным на малой скорости, чем турбореактивный двигатель?
Турбовентиляторный двигатель легче, менее экономичен на малых скоростях и более экономичен на больших скоростях по сравнению с турбовинтовым двигателем, не так ли?
На каких самолетах устанавливается турбовентиляторный двигатель?
Задание 12. Письменно переведите текст без словаря.
In the turbofan, also called the bypass engine, the exhaust gases actually are expelled from the rear nozzle at a slower velocity than a turbojet engine. This decreased velocity would provide less thrust. But the amount of air passing through a turbofan engine is much larger than that passing through a turbojet, and results in a much greater push. Though the turbofan engine takes in much greater quantities of air, only about half of it is pumped into the combustion chamber, while the remainder is ducted, actually with a lower fuel consumption, than the turbojet engine.
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