questions and formula

Question 1

gross thrust formula

Answer 1

(ṁ_{exit air} * v_{exit air}) + (ṁ _fuel * v_{exit air}) + ΔP * A

Question 2

net thrust formula

Answer 2

gross thrust - ṁ_{inlet air} * v_{inlet air}

Question 3

Which are the two functional elements in a centrifugal compressor?

Answer 3

impeller & diffuser

Question 4

The highest heat-to-metal contact in a jet engine occurs in the?

Answer 4

nozzle guide vane

Question 5

impulse blade mechanical energy extracted & velocity of air high or low?

Answer 5

mechanical energy: high

velocity of air: low

Question 6

An exhaust placed aft of the turbine in a turbojet engine will cause

Answer 6

pressure decrease, velocity increase

Question 7

The exhaust section of a turbine engine is designed to

Answer 7

impart high velocity to gas

Question 8

What is the purpose of incorporating a synchrophasing system on a turboprop engine?

Answer 8

reduce noise & vibration

increase passenger comfort

Question 9

The blade angle on a turboprop engine changing using

Answer 9

hydraulic pressure

Question 10

What is the purpose of feathering the propeller blades on a multi turboprop engine?

Answer 10

reduce drag & yaw effect

Question 11

How does the propeller brake remain in the released?

Answer 11

oil pressure

Question 12

What is the purpose of a shear pin?

Answer 12

shear off when engine fitted incorrectly

alignment