Gas Turbines - The Turbine Assembly: DGCA Technical General questions

Question 1

Blade creep is:

Accepted Answer

permanent elongation due to heat and centrifugal force.

Answer

movement of the turbine blades around the turbine disc.

Answer

temporary expansion due to temperature change.

Answer

temporary elongation due to centrifugal forces.

Question 2

A free power turbine:

Accepted Answer

has no mechanical connection with the other turbine or compressor shafts.

Answer

has a clutch between the compressor and the power output shaft.

Answer

has a direct drive with a free wheel unit.

Answer

comes free with every 2000 gallons of AVTUR.

Question 3

The effect on the temperature and pressure of the gases as they pass across the turbine is:

Accepted Answer

both their temperature and pressure decrease.

Answer

their temperature decreases and their pressure rises.

Answer

both their temperature and pressure increase.

Answer

their temperature increases and their pressure falls.

Question 4

The mixture of impulse and reaction blade shape in the average turbine blade is such that:

Accepted Answer

the inner half is impulse and the outer half is reaction.

Answer

the inner half is reaction and the outer half is impulse.

Answer

the leading edge is reaction and the trailing edge is impulse.

Answer

the trailing edge is reaction and the leading edge is impulse.

Question 5

The impulse-reaction blade is twisted along its length so that:

Accepted Answer

the gas does equal work along the whole of its length.

Answer

there is a greater angle at the base than at the tip.

Answer

the gas flow is accelerated through the turbine.

Answer

the gas flow is decelerated through the nozzle guide vanes.

5 more questions in this chapter, free with an account