While gas turbines exist in many different designs, every gas turbine has three major components, compressor section, combustion section, and:
Turbine section
Shell section
Steam section
Low pressure section
High pressure section
Ambient air entering the combustion chamber is first pressurized to about (?) Kpa
50 to 100
500 to 1000
1100 to 3000
3000 to 5000
5000 to 10000
In the single shaft arrangements the compressor, turbine and load are all connected and rotate
Opposite of one another
Counterclockwise
Clockwise
Together
None of the above
A disadvantage of a closed style gas turbine is:
Cooling water is needed
The working fluid is dirty
Only cheap fuel can be used
The working fluid may support combustion
Low pressure, Low output
A gas turbine installation involves a number of additional components, systems and equipment that vary widely depending on the type of gas turbine, its location, environmental conditions and:
Cost
Size
Application
Pressure rating
Many gas turbines are contained in an enclosure that protects it from the environment, provides protection for personnel in case of failure and:
Keeps costs down
Keep it clean
Prevent damage
Reduce noise
Modern gas turbines are able to reach efficiencies of (?) in simple cycle mode without the cycle improvements or combined cycle:
5-10%
15-20%
25-30%
35-40%
45-50%
On a gas turbine the most common cycle improvements to be made is:
Inter cooling
After cooling
Reheating
Combined cycle
Regeneration
A highly efficient and capable compressor is critical for the efficient operation of a gas turbine. Two types of compressors are used in gas turbines are Centrifugal and:
Differential
Positive flow
Negative flow
Radial
Axial
Advantages of the radial or compressor are simplicity, short length and:
Strength
Noise reduction
Power
For a gas turbine there are three basic designs for combustors. The can-annular, annular and:
Annular-can
Can
Single can
Double can
About (?) per cent of the air entering the combustor is mixed with the fuel in the flame tube as combustion air; the remainder flows on the outside of the tube and services as cooling air.
10
20
30
40
50
Turbines can be of the axial-flow or (?) type:
Differential flow
Radial flow
Radial inflow
Axial inflow
What is used in blade cooling on a gas turbine?
Air
Oxygen
Nitrogen
Fans
All of the above
An automatic emergency trip system closes the main fuel shutoff valve if:
The Lubricating oil pressure drops to an unsafe pressure
The exhaust temperature exceeds the allowable limit
Either of the rotor speed becomes excessive
A number of protective devices will first alarm and then shutdown the engine if certain levels are exceeded. They normally protect against:
Power turbine overspeed
Exhaust gas temperatures higher than the maximum limit
Excessive vibration
Excessive oil and bearing temperatures
The temperature of the air entering the gas turbine has a great impact on its operation and performance. As the air temperature decreases, its
Density decreases
Density increases
Pressure increases
Pressure decreases
A gas turbine will produce more power at:
Higher temperatures
Lower temperatures
Higher pressures
Lower pressures
All lubricating systems provide two basic functions, to lubricate sliding surfaces in the bearing and:
Keep the bearing clean
Cool the bearings
Keep water away
Reduce corrosion
Gas turbines use two different types of bearings, Antifriction bearings and:
Greased bearings
Roller
Ball
Rotor
Maintenance of fuel gas systems are relatively maintenance free and automatic protection is usually provided. Maintenance operators may do consist of:
Checking for fuel gas leaks
Monitoring pressure and temperature
Changing fuel filters
Calibrating instrumentation and testing protective devices
Fuel for a gas turbine that would promote the most efficient combustion and produce the lowest environmental emissions world be:
Methane
Ammonia
Natural gas
Fuel gas
Kerosene
A gas turbine can operate on a wide range of liquid fuels such as blended heavy distillantes, residuals and heavy ash crudes, and:
Distillantes
Blended ash crudes
Low ash crudes
A liquid fuel which requires considerable cleaning and treatment would be:
Distillants
Blended heavy distillants
Heavy ash crudes
NOx Emissions are formed during combustion from the reaction of:
Water or steam
Soda ash
Lime
What system can be used to provide the initial rotation of the main compressor?
Pneumatic starters using compressed air or gas
Electric motors
Small diesel engines
Steam turbine expanders
What problems to sagging or bowing cause in a gas turbine?
Prevent start up
High vibration
Excessive heat
A and B
Various methods of inlet cooling used today are spray cooling, fog cooling and:
Special evaporative pads
Steam cooling
Water pan cooling
Forced Air cooling
Natural air cooling
Anti-icing systems may operate by:
Beating off the ice
Installing heating coils
Feeding heated air from some other source into air intake
B and C
In an internal combustion engine what are the three major types of fuels?
Gasoline, Diesel, and kerosene
Gasoline, Natural gas, Gaseous fuels
Gasoline, Fuel oils, and Diesel
Gasoline, Gaseous fuels, and Fuel oils
For a normal shutdown of a gas turbine the procedure is basically the reverse of a startup procedure.
When a fast shutdown for a gas turbine has been initiated the cooldown period is eliminated and the fuel valve is closed immediately.
To perform an off-line waterwash, the engine is stopped and does not need to cool first.
To perform an on-line wash the gas turbine is slowed slightly and has no need to cool.
One major difference in a diesel engine compared to the gasoline engine is:
One engine is larger then the other
Gasoline engines do not require a spark for ignition
Gasoline engines require compression for ignition
Diesel engines do not require a spark for ignition
How many camshafts are there in a Combustion engine?
1
2
3
4
5
A cylinder head on a combustion engine is made of:
Special Heat resisting cast iron
Aluminum
Steal
Heat treated nickel iron alloy
Heat treated Steal
