AIRCRAFT INLE
23/10/2023
, Inle
• Inlets are very important to the overall jet engine performance & will
greatly influence jet engine thrust output.
• The faster the airplane goes the more critical the inlet duct design becom
• Engine thrust will be high only if the inlet duct supplies the engine with th
required airflow at the highest possible pressure.
• The nacelle/duct must allow the engine to operate with minimum
stall/surge tendencies & permit wide variation in angle of attack & yaw o
the aircraft.
• For subsonic aircraft, the nacelle shouldn’t produce strong shock waves o
flow separations & should be of minimum weight for both subsonic &
supersonic designs.
• For certain military applications, the radar cross sectional control or rada
reflectance is a crucial design requirements.
23/10/2023
, • It must operate from static ground run up to high aircraft Mach
number with high duct efficiency at all altitude, attitudes & fligh
speeds.
• It should be as straight & smooth as possible & designed such a
way that Boundary layer to be minimum.
• It should deliver pressure distribution evenly to the compressor.
• Spring loaded , blow-in or such-in-doors are sometimes placed
around the side of the inlet to provide enough air to the engine
high engine rpm & low aircraft speed.
• It must be shaped such a way that ram velocity is slowly &
smoothly decreases while the ram pressure is slowly & smoothly
increases.
23/10/2023
23/10/2023
, Inle
• Inlets are very important to the overall jet engine performance & will
greatly influence jet engine thrust output.
• The faster the airplane goes the more critical the inlet duct design becom
• Engine thrust will be high only if the inlet duct supplies the engine with th
required airflow at the highest possible pressure.
• The nacelle/duct must allow the engine to operate with minimum
stall/surge tendencies & permit wide variation in angle of attack & yaw o
the aircraft.
• For subsonic aircraft, the nacelle shouldn’t produce strong shock waves o
flow separations & should be of minimum weight for both subsonic &
supersonic designs.
• For certain military applications, the radar cross sectional control or rada
reflectance is a crucial design requirements.
23/10/2023
, • It must operate from static ground run up to high aircraft Mach
number with high duct efficiency at all altitude, attitudes & fligh
speeds.
• It should be as straight & smooth as possible & designed such a
way that Boundary layer to be minimum.
• It should deliver pressure distribution evenly to the compressor.
• Spring loaded , blow-in or such-in-doors are sometimes placed
around the side of the inlet to provide enough air to the engine
high engine rpm & low aircraft speed.
• It must be shaped such a way that ram velocity is slowly &
smoothly decreases while the ram pressure is slowly & smoothly
increases.
23/10/2023
