Turbine Engine Intake Systems Flashcards
What are the ideal characteristics of a turbine engine intake?
To deliver the air to the compressor evenly, with no turbulence and at higher than ambient pressure.
What is the shape formed by the duct of an intake on a turbofan powered subsonic aircraft and why?
Divergent, to convert kinetic energy into pressure energy.
What is RAM effect?
The pressurisation of the air entering the intake caused by the aircraft’s forward speed.
What is the most common type of intake on turbofan engines?
Pitot type.
What is the disadvantage of using a divergent intake duct?
Separation of the boundary layer on the duct walls.
What are the disadvantages of a long intake duct?
Too much drag, with a resulting loss of efficiency.
What is the primary disadvantage of divided entrance intakes?
The potential for interference to the flow when the aircraft yaws.
Why do some turboprop and Turboshaft engines have shrouds or screens over their intakes?
To reduce the possibility of ingesting birds, dust, sand, and other FOD.
How do supersonic air intakes decelerate the air to subsonic speeds prior to compressor entry?
By creating shockwaves through which the airflow passes, thereby increasing its pressure, density and temperature and decreasing its velocity.
