Module 2 Part 3

Front 1

What does a gas turbine engine do?

Back 1

Takes in air, adds energy to it, then discharges it to produce thrust.

Front 2

An engine takes in hoe much air per second?

Back 2

1200 kilograms

Front 3

At what speed do blades of a compressor rotate at?

Back 3

1600 kph

Front 4

By how much does a modern compressor need to inrease ambient air pressure against ambient air pressure?

Back 4

About 40 times

Front 5

How fast does a compressor need to move air?

Back 5

400 to 500 feet per second

Front 6

How can you measure compressors effectiveness

Back 6

Ratio of air pressure at compressors discharge to air pressure at inlet.

Front 7

Secondary function of compressor

Back 7

Supplies bleed air to cool the hot section and heated air for de-icing.

Front 8

Auxilary functions of compressor

Back 8

-cabin pressurization

-air conditioning

-fuel system de icing

-pneumatic engine starting

Front 9

Two basic types of compressors

Back 9

-centrifugal flow compressor

-axial flow compressor

Front 10

A synonym of a centrifugal compressor

Back 10

Radial outflow compressor

Front 11

What does a centrifugal compressor consist of?

Back 11

-rotor (impeller)

-diffuser

-manifold

Front 12

Impellers function is

Back 12

To take in air and accelerate it outward by centrifugal force.

Front 13

How many impellers do centrifugal compressors have?

Back 13

One or two

Front 14

Centrifugal compressors having a one impeller

Back 14

Single stage compressors

Front 15

Centrifugal compressors having two impellers

Back 15

Double stage comlressors

Front 16

An impeller (rotor) consists of

Back 16

A forged disk with integral blades, fastened by a splined coupling to a common power shaft.

Front 17

Diffuser function

Back 17

Acts as a divergent duct, where air spreads out, loses velocity and increases pressure.

Front 18

How does air exit rotor?

Back 18

Air is expelled into a diffuser

Front 19

Function of manifold

Back 19

Distribute air in a smooth flow to the combustion section

Front 20

How does a manifold maintain uniform air supply to combustor?

Back 20

It has one outlet port for each combustion section.

Front 21

Where are the compressor outlet elbowsbolted to?

Back 21

To the each of the outlet ports (outlet ducts), (combustion chamber inlet ducts)

Front 22

Advantages of centrifugal compressors

Back 22

-simplicity

-cheap

-light

-efficiency

Front 23

Disadvantages of centrifugal compressors

Back 23

-large frontat area, which increases drag.

Front 24

Rotor consists of

Back 24

Rows of blades fixed on a rotating spindle.

Front 25

What do blades do due to their angle?

Back 25

Force the air rearward due to angle

Front 26

What do stator vanes do?

Back 26

Act as diffusers

Front 27

Where are stator vanes?

Back 27

Arranged in fixed rows between rows of rotor blades.

Front 28

What is a pressure stage?

Back 28

Each row of rotor blades and stator vanes.

Front 29

Task of axial compressor

Back 29

Raises pressure not air velocity

Front 30

What happens to air velocity/pressure in compressor

Back 30

Airfow velocity constant, pressure increases

Front 31

Advantages

Back 31

Low frontal area

Front 32

Disatvantages

Back 32

-high weight

-high starting reqs

-expensive

-difficult