Turbine Engines Flashcards
What are the major components of a typical gas turbine engine?
An air inlet, compressor section, combustion section, turbine section, exhaust section, and accessory section.
What determines the amount of air passing through a turbine engine?
Compressor speed, forward speed of the aircraft, and air density.
What are the two principle types of compressors currently used in turbine engines?
Centrifugal and axial flow.
How are turbine engine rotor blades attached to rotor disks? (Name at least two methods.)
By a: (1) bulb-type root, (2) fir tree-type root, or (3) dovetail-type root.
What is the purpose of interconnect tubes attached between can-type combustion chambers?
For flame propagation during starting.
What prevents burning of combustion chambers?
Cooling air along the inside of the liner?
What are the functions of axial flow turbine nozzles?
They prepare the mass airflow for driving the turbine rotor and deflect the gases to a specific angle.
What are some ways of relieving thermal stress on a turbine disk?
By directing bleed air on to the face of the disk, or by the grooving in the turbine disk.
What are the carbon seals used for in turbine engines?
As oil seals for the rotor shaft bearings.
What is the main operating difference between turbofan and turbojet engines?
The air that flows through the fan section of a turbofan engine bypasses, or flows around, the outside of the core engine instead of through it.
Name an advantage of a turbofan over a turbojet.
Additional thrust without increasing fuel flow.
What type of compressor blade damage may be found when inspecting compressor blades?
Dents, galling, pitting, cracks, scratches, burrs, burns, and gouges.
What is the effect of relative humidity on turbojet or turbofan power?
Negligible.
What may be the indications if a turbojet or turbofan engine is out of trim?
The engine has high exhaust gas temperature at the target engine pressure ratio for takeoff power.
What would the possible cause be for a turbojet or turbofan engine having high exhaust gas temperature, low RPM, and high fuel flow at all engine pressure ratio settings?
Possible turbine damage or loss of turbine efficiency.
