問題一覧
1
Axial flow compressors have a pressure rise per stage of approximately __________:1.
1.25
2
___________ vane segments may be used to minimize vibration.
shrouded
3
Bypass ratios of 30:1 are obtainable by what is called an __________High Bypass (UHB) engine.
Ultra
4
Multi-spool axial flow compressors have the advantages of: a. __________ b. __________ c. __________ d. __________
better performance at high altitudes, ability to obtain higher compression ratios, small frontal area, high fan efficiency
5
The four types of gas turbine engines are the __________, __________, __________, and the __________.
turboshaft, turbojet, turbopro peller, turbofan
6
When subsonic air passes through a section of a duct that has a divergent shape, its velocity will __________ (increase or decrease).
decrease
7
A high bypass ratio turbofan engine has a bypass ratio __________ of to 1 or greater.
4
8
With modern high bypass engines, most of the engineís thrust is produced by the __________ rather than from the __________ exhaust __________.
fan, jet thrust
9
Modern centrifugal compressors can obtain a compression ratio as high as _______:1.
15
10
What is the primary function of the compressor section of a gas-turbine engine?
to supply enough air to support combustion and produce thrust
11
The stationary elements of an axial flow compressor are referred to as __________ (blades or vanes).
vanes
12
The two basic types of compressors used on turbine engines are: a. __________ b. __________
centrifugal, axial
13
Turbofans are generally divided into what three classifications? a. __________ b. __________ c. __________
low bypass, medium bypass, high bypass
14
The rotating elements of an axial flow compressor are referred to as __________ (blades or vanes).
blades
15
Compressor blades which have a reduced thickness at the tips are called ___________ tips.
profile
16
The inlet duct of a turbine engine is normally considered to be a part of the ____________ (airframe or engine).
airframe
17
Jet propulsion is a practical application of Newton’s __________ (first, second, or third) law of motion.
third
18
. Engines that use a separate turbine that is not mechanically connected to a compressor to drive a propeller are called __________ __________ engines.
free turbine
19
The first flight by a jet propelled aircraft took place in __________ (what year).
1939
20
The two main elements of an axial flow compressor are: a. __________ b. __________
rotor, stator
21
Supersonic aircraft typically utilize a __________-__________ inlet duct.
diverging, converging
22
What is the primary function of the compressor section of a gas-turbine engine?
to supply enough air to support combustion and produce thrust
23
Subsonic inlet ducts are usually of a fixed geometry and __________ (converging or diverging) in shape.
diverging
24
More than __________(what number) stages of compression is not practical using a centrifugal compressor.
2
25
Both turboprop and turboshaft engines must use a between the engine and the propellers/rotors.
reduction gearbox
26
A gas turbine engine that delivers power through a shaft to operate something other than a propeller is referred to as a __________ engine.
turboshaft
27
The three main components of a centrifugal compressor are: a. __________ b. __________ c. __________
impeller, diffuser, manifold