Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

M15✅ > 15.7 EXHAUST👌🏼 > Flashcards

15.7 EXHAUST👌🏼 Flashcards

1
Q

In general, the exhaust system does what?

A
  • guides exhaust gases from rear of turbine into atmosphere
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

On a jet engine, what is the exhaust system for

A
  • to accelerate airflow coming from turbine
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the main task of the exhaust system in the turboprop engine

A

Safely guide exhaust gases overboard

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the exhaust system of the APU for

A

Guides exhaust gases overboard because all the gas energy will be absorbed by the turbine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

How is the APU noise of the exhaust system reduced

A
  • through mufflers in the exhaust duct
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

List the 3 components of the exhaust section

A
  • exhaust cone
  • tailpipe
  • exhaust nozzle
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Explain the exhaust cone

A
  • collects exhaust gases from turbine section
  • velocity of gases is decreased slightly, pressure increases
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the function of the radial hollow struts in the exhaust cone assembly

A
  • support inner cone
  • straightens swirling exhaust gases that would leave turbine at 45* angle
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the function of the small hole located at the exit tip of the cone

A
  • cooling air circulated from the aft end of cone
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

The tail-pipe is usually constructed so that it is semi-flexible (T OR F)

A

T

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the 2 suitable methods of protecting fuselage structure

A
  • insulation blankets (most common)
  • Shrouds
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What does the insulation blanket consist of

A
  • several layers of aluminium foil separated by a layer of fibreglass
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the primary reason of the insulation blanket

A

Reduce heat loss from exhaust system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the 2 types of exhaust nozzles

A
  • Converging (subsonic)
  • Converging-diverging (supersonic)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Why is there a converging nozzle before exhaust gases are discharged

A
  • so velocity can be increased
  • producing 15%-20% extra thrust
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Turboprop exhaust nozzle produce how much thrust

A

10%-15%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

The turboprop nozzle is mainly used for what

A

Discharge exhaust gases from aircraft

18
Q

On turboprop, the exhaust nozzle is also referred as ?

A

Tailpipe

19
Q

When would a variable area exhaust nozzle be used

A
  • when augmenter or afterburner is used
    -due to increased mass flow when afterburner is activated
20
Q

Convergent duct increases gas velocity, therefore providing more thrust (T or F)

A

T

21
Q

Why would you use a convergent-divergent duct

A
  • when EPR is high (>MACH 1)
  • more thrust can be gained
22
Q

In a C-D nozzle, what is the convergent section for

A

Designed to handle gases while they remain subsonic

23
Q

In a C-D nozzle, what is the divergent section for

A
  • further increases velocity
  • becomes supersonic
24
Q

What is the common type of noise suppressor used

A
  • integral, airborne part of aircraft engine installation
  • engine exhaust nozzle
25
Q

How is the noise produced by the engine exhaust

A
  • caused by high degree of turbulence of high velocity jet stream
26
Q

Large engines operating at partial thrust are less noisy than smaller engines operating at full thrust

A

True

27
Q

What are the 2 types of noise suppressors

A
  • corrugated perimeter type
  • multi- tube type
28
Q

In the engine nacelle, the area between engine and the cowl has what

A
  • ## acoustic linings (converts energy into heat)
29
Q

Explain the construction of the acoustic linings

A
  • consist of porous skin supported by honeycomb backing
30
Q

Explain thrust reverser

A
  • braking force by deflecting exhaust gas stream in opposite direction
31
Q

On modern turbofan engines which airflow is reversed

A
  • fan airflow reversed as this creates most of the engines thrust
32
Q

What are the 2 types of thrust reverser

A
  • Clamshell
  • bucket
33
Q

Explain clamshell type thrust reverser

A
  • older jets with low bypass ratio
  • usually pneumatically operated by bleed air
34
Q

Explain bucket type thrust reverser

A
  • older jets with low bypass ratio
  • usually hydraulically operated
35
Q

On turbofan engines what air is deflected to give reverse thrust

A

Fan air

36
Q

Fan reversers are most commonly what type of thrust reverser

A

Cascade type

37
Q

In a turbo fan what are the blocker doors function

A
  • ensure all fan air is discharged through cascade vanes
38
Q

How are the pivoting door reversers operated

A

Hydraulically

39
Q

Why should you not use thrust reversers at low speeds

A
  • Engine will ingest its own reversed airflow
  • Cause compressor stall and high EGT
40
Q

At what speeds should thrust reversers be activated

A
  • high speeds
41
Q

To minimise disadvantages caused by reverser operation, the reversed airflow is matched to engine position .(T or F)

A

True

42
Q

Explain thrust vectoring

A
  • for manoeuvring in flight to change direction

M15✅ (16 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions