Design and analysis of a supersonic axisymmetric inlet based on controllable bleed slots

Abstract

Aiming at the problem of starting and inlet-engine matching of axisymmetric variable geometry inlet with complex structure, a novel design concept of axisymmetric inlet is proposed based on controllable bleed slots switch. The laws of the typical geometric parameters of multi-slots effecting on inlet start, supercritical and subcritical performances are numerically studied. Accordingly, a three-dimensional aerodynamic design scheme of the inlet operating at Ma1.5-4 and control laws of the bleed slots are gained, which is slightly altered inlet surface and structure is simplified. The aims of minimum starting Mach number to 2 and inlet-engine matching inlet are achieved by controlling switch of bleeding slots, and inlet operates well at high total pressure recovery and low exit Mach number. The results show that: at Ma=2, the inlet starts with 30% bleeding and 16.5% total pressure recovery coefficient improving; At Ma=3, mass flow of inlet-engine matches with 23% subsonic bleeding but cost of total pressure loss about 2.6%.