Gas Turbines - Introduction: DGCA Technical General questions

Question 1

A pure turbojet engine gives:

Accepted Answer

A large acceleration to a small mass of air.

Answer

A small acceleration to a large mass of air.

Answer

A large acceleration to a large mass of air.

Answer

A small acceleration to a small mass of air.

Question 2

Aft of the compressor:

Accepted Answer

The velocity of the airflow decreases before the combustion chamber.

Answer

The velocity of the airflow remains the same.

Answer

The velocity increases before the combustion chamber.

Answer

The air pressure decreases before the combustion chamber.

Question 3

A Bypass Ratio of 5:1 means that:

Accepted Answer

5 pounds of air is bypassed for every 1 pound that goes through the hot core of the engine.

Answer

5 pounds of air is bypassed for every 10 pounds entering the engine intake.

Answer

5 pounds goes through the HP compressor for every 10 pounds that enters the intake.

Answer

10 pounds of air goes through the bypass for every 5 pounds that enters the intake.

Question 4

During the Brayton cycle, combustion takes place:

Accepted Answer

Continuously.

Answer

Once every revolution.

Answer

Once every other revolution.

Answer

Only during the start cycle.

Question 5

In a turbofan engine, the fan speed is controlled by:

Accepted Answer

The turbine.

Answer

A reduction gear.

Answer

A wastegate.

Answer

Varying the pitch.

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