Powerplant IV Mod 1 quiz

Turbine Engine Construction/ Types of Turbine Engines

Which section of a gas turbine engine is responsible for driving the fan?

Turbine section

Which type of gas turbine engine is most efficient in the 300 to 400 mph speed range?

Turboprop

What is the purpose of convergent and divergent shaped ducts in supersonic inlets?

To control and drop the air flow to subsonic speeds

What is the role of increasing the forward speed of the aircraft in determining the amount of air passing through a gas turbine engine?

It increases the amount of air passing through the engine

What is the role of increasing the density of the ambient air in determining the amount of air passing through a gas turbine engine?

It increases the amount of air passing through the engine

What is the primary function of the accessory section in a gas turbine engine?

To provide space for mounting accessories

Where is the accessory gear box typically located in a turbofan engine?

On the bottom of the engine

Where is bleed air typically extracted from in a gas turbine engine?

The compressor outlet

What is the purpose of the diffuser in a centrifugal-flow compressor?

To compress air while it continues in its original direction of flow

Where is the combustion section located in relation to the compressor and turbine sections?

 

Directly between the compressor and turbine

What is the purpose of the fuel drainage system in a combustion chamber?

To drain off unburned fuel after engine shutdown

Which type of combustion chamber is typically used on turboshaft and APUs?

Can-type

What is the purpose of the shroud in an annular combustion chamber?

To prevent flame contact with the combustion chamber

What is the purpose of the pre-swirl vanes in a can-annular combustion chamber?

To provide a swirling motion to the fuel spray

What are the advantages of using an annular combustion chamber in modern turbine engines?

Both Answers are correct

Higher efficiency AND Better atomization of fuel

What is the purpose of the gas generator turbine?

To absorb kinetic energy from the exhaust gases

Which type of turbine blade is also referred to as a bucket?

 

Impulse turbine blade

What is the function of the turbine inlet nozzle assembly?

To deflect gases in the direction of turbine rotation

What is the function of the turbine nozzle guide vanes?

To increase the efficiency of the air stream striking the blades

What is the difference between the turbine inlet nozzle assembly and turbine nozzle guide vanes from the previous questions?????

 

Different names for the same component

What material is commonly used for the turbine shaft?

Steel

What is the benefit of using single crystal blades?

Better strength and heat properties

Why would it be necessary to use multiple turbine stages?

To drive heavy rotational loads

What is the purpose of the thermocouple bosses in the outer shell or duct of the exhaust section?

To measure exhaust temperature

What are the principles of convergent and divergent ducts for subsonic gas velocities? 

Convergent increases velocity and decreases pressure, while divergent decreases velocity and increases pressure