The Origin of Aerodynamic Instability of Supersonic Inlets at Subcritical Conditions

Abstract

Memorandum presenting an investigation of the phenomenon of the starting of aerodynamic instability or buzz in supersonic inlets with external compression. The starting of the buzz has been related to the existence in the flow field of a velocity discontinuity across a vortex sheet which originates at a shock intersection. Results regarding the inlets without separation on the central body, inlets with separation on the central body, the regulation of entering volume flow at angles of attack, experimental performance of various inlets, and an application of the results are provided.