| has gloss | eng: An intake ramp is a rectangular, plate-like device within the air intake of a jet engine, designed to generate a shock wave to aid the inlet compression process at supersonic speeds. The ramp sits at an acute angle to deflect the intake air from the longitudinal direction. At supersonic flight speeds, the deflection of the air stream creates an oblique shock wave at the forward end of the ramp. Air crossing the shock wave suddenly slows to a lower Mach number, thus increasing pressure. However, shock waves are non-isentropic, so there is a reduction in total, or stagnation pressure relative to that of the free air stream. Although there are reflected oblique shock waves and a weak normal shock wave generated downstream, this form of intake is more efficient (i.e. higher total pressure recovery) than the equivalent pitot intake, particularly at high supersonic flight speeds. |
