Chapter 2: Inlet Flashcards
engine inlet qualities
1) adequate mass flow rate at proper mach number
2) spatially smooth flow into compressor
3) low installation drag
4) acoustic absorption
5) FOD control for vertical lift aircraft
what happens when aircraft yaws?
uneven ram air for both intake
what is the ideal mach number for entry flow for both subsonic and supersonic aircraft?
M0.4 - M0.5
what can non uniform flow cause?
compressor surge/stall
what does compressor stall/surge lead to?
engine flameout or mechanical vibration
what does the propeller help with the airflow?
increase speed of air going into compressor
velocity and pressure stats for convergent divergent duct for supersonic intake
velocity drops all the way
pressure increases all the way
air is subsonic at throat
locations that icing will occur on engine
1) nose cone
2) inlet strut
3) inlet guide vane
4) nose cowl
what does icing do to engine?
1) distort and restrict incoming airflow > result in reduced thrust and increase compressor stall/surge
2) ice can break resulting in FOD on compressor
what is anti-icing and de-icing?
anti-icing: prevent ice from forming
de-icing: breaking of ice after formed
anti-icing methods
1) pneumatic thermal
2) electrical thermal (for nose cowling)
3) hot oil (from bearing lubrication)
de-icing methods
dynamic ice shredder
what kind of inlet duct is good for subsonic aircraft?
divergent duct (pressure increases)
