Experimental Investigation of Dynamic Separation for an Inlet Cover in Mach 6.0 Flow

摘要

Inlet cover or shroud, which can avoid the influences of inlet unstart in a low Mach number flight, is widely used in high-speed vehicles, especially in an axial symmetry aerodynamic configuration. The feasibility and safety of cover separation is crucial for flight vehicle. Hence, a special care is devoted to cover separation. Under the capability limitation of the ground facilities, the cover separation has been relied solely on numerical simulation which is insufficient in simulation reality so far. In this article, the critical points of dynamic separation experiments in high-speed flow, such as similarity criterion, tunnel protection and trace observation, were analyzed in detailed. Then, a dynamic separation experiment in Mach 6.0 flow was conducted in the shock tunnel for a simplified forebody with an inlet cover. The separation trace was obtained by distinguishing the cover edge from recorded high-speed pictures. The separation trace obtained by experiment is accordant with CFD results, and the separation time just differs about 2ms. The success of separation experiment and the agreement of separation trace verify the feasibility and accuracy of the experiment method presented in this article.