Statistical analysis method for prediction of maximum inlet distortion

Abstract

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The Origin of Inlet Buzz in a Mach 1.7 Low Boom Inlet Design

“…Firstly, in Phase (1) at low spillage (critical operating condition), a high frequency low amplitude oscillation of the normal shock exists. The inlet Mach number contours for Phase (1) inlet operation are shown in Figures (4) through (6). This is succeeded by Phase (2) in Figure (3), as the back pressure is further increased (subcritical operation), to a high frequency higher amplitude oscillation which is stable and dominated by the development of separation bubbles at the normal SWBL interaction on the isentropic spike.…”

“…That is because the process described from this analysis is fundamentally stochastic and not deterministic. There are however, in the body of literature, approximate statistical assessments of dynamic-distortion levels (5)(6)(7)(8) . This involves the measurement of the steady state total pressures and the RMS of the time varying total pressures using some or all of the rake probes at the Aerodynamic Interface Plane (AIP) station downstream inlet.…”