15.1, 15.3, 15.4

Question 1

Force

Answer 1

Mass x acceleration

Question 2

Work

Answer 2

Force x distance

Question 3

Power

Answer 3

Rate at which work is performed

Work/time

Question 4

Velocity

Answer 4

Rate if change

Question 5

Turbo jet vs turbo fan

Answer 5

Turbofan is bypassed

Question 6

2 parts of a spool

Answer 6

Compressor , turbine

Question 7

Advantage of high bypass engine

Answer 7

Lower noise level

Question 8

Specific fuel consumption

Answer 8

Pounds of fuel burned per hour to produce one unit of thrust

Question 9

Ram ratio

Answer 9

Compression inlet pressure / ambient pressure

Question 10

Variable geometry intake

Answer 10

Supersonic intake

Question 11

Where is bell mouth intake used

Answer 11

Helicopter and APU

Question 12

3 types of subsonic air inlet

Answer 12

Pitot , s duct , bell mouth

Question 13

Duct best for supersonic engine

Answer 13

CD duct , variable geometry duct , moveable wedge intake

Question 14

Bifurcated duct

Answer 14

Used on transonic military aircraft

Question 15

2 types of compressor

Answer 15

Axial flow ; centrifugal flow

Question 16

Compressor pressure ratio

Answer 16

Pressure of air outside vs inside

Question 17

Where does pressure rise occur in centrifugal compressor

Answer 17

50% in impeller rest in vaneless space

Question 18

Advantages of centrifugal compressor

Answer 18

High pressure rise per stage
Good efficiency
Simplicity of manufacture

Question 19

3 types of axial flow compressor

Answer 19

Single , dual , triple

Question 20

Spool?

Answer 20

Compressor being driven by a turbine

Question 21

What is a stage

Answer 21

A complete stage is a row of rotor blades followed by a row of stator blades

Question 22

Components of axial flow compressor

Answer 22

Rotor , stators, rotor shaft , rotor discs , rotor blades

Question 23

Compressor stall

Answer 23

Happens when there’s an imbalance of compressor RPM

Question 24

What happens temp pressure and velocity in a compressor

Answer 24

Temp and pressure increase , velocity decrease

Question 25

What does air passing through a compressor depend on

Answer 25

Air density , aircraft speed , engine RPM

Question 26

Effect of temp on pressure rise

Answer 26

Low temp = greater pressure rise

Question 27

Parts of centrifugal compressor

Answer 27

Impeller rotor , diffuser , manifold

Question 28

Why are stator vanes shrouded

Answer 28

Prevent vibration

Question 29

Purpose of bleed valves

Answer 29

Prevent engine surge

Question 30

Tip clearance control

Answer 30

Cool and hot air contracts or expands tip to maintain clearance