Engine Exhaust and Reverser Systems Flashcards
Of what material are most reciprocating engine exhaust components made?
Corrosion Resistant Steel
How is the speed of a turbocharger controlled?
By controlling the amount of exhaust gas that slows through the turbine. This is controlled by the position of the waste gate that is in the exhaust pipe
What type of actuator is used to control the position of the turbocharger waste gate?
A hydraulic actuator that uses engine oil pressure to move the piston
How does a power recovery turbine increases the power of a reciprocating engine?
Exhaust driven velocity turbines are coupled through a hydraulic drive to the engine crankshaft. Energy that would normally be lost is used to drive the turbines, and the turbines assist in turning the crankshaft
How tight should the clamps be tightened that hold sections of a reciprocating engine exhaust system together?
They should not be so tight that they will be damaged when heat expands the exhaust system components
What would be the effect on engine performance of an internal failure of a muffler?
This will increases the exhaust back pressure and causes a loss of engine power
What effect on turbine engine operation is caused by a change in the area of the exhaust nozzle?
Altering the area of the exhaust nozzle affects the compression ratio, the RPM, the mass airflow through the engine, and the EGT
What are two types of thrust reversers that are used with turbojet engines?
Mechanical blockage (clamshell) and aerodynamic blockage (cascade)
How does a noise suppressor reduce the amount of noise produced by a turbojet engine?
It breaks up the low frequency vibrations in the exhaust stream and converts them into higher frequencies. These high frequencies are dissipated by the air more easily than low frequencies
What is the purpose of the ball joints and bellows in the exhaust system of a reciprocating engine?
The ball joints and bellows allow the exhaust system components to change their dimensions without causing any leaks
Why do some supersonic aircraft use a convergent-divergent exhaust duct?
A CD exhaust duct controls the gas expansion as it leaves the engine so the gases will produce thrust at supersonic velocities
Why is it important that a lead pencil never be used to mark on an aircraft exhaust system?
The graphite in a lead pencil will infuse into the metal when it gets hot. It makes the metal brittle and likely to crack
What type of damage is normally found in the hot section of a turbine engine?
Cracks caused by heat
