Shock – Wave– Boundary– Layer Interaction (SWBLI) around Open Flaps of Expert Capsule and their Consideration on Heat and Mechanical Loads under Critical Re-entry Flow Conditions

Abstract

In the frame of EXPERT project DLR is proposing a flight experiment on shock-wave boundary-layer interaction (SWBLI) with shear-layer reattachment on control surfaces to improve our understanding about flap efficiency and heating due to high temperature 3D effects, radiation-cooling effects, transition, turbulence (unsteadiness) and strong viscous hypersonic interaction. The objective of the present work is applying CFD to estimate for the most critical flight condition the maximal aerothermodynamic loads on the capsule surface, with a special emphasis on the flaps and their surrounding. The very important questions to be answered for the design of the flaps are the determination of the magnitude and location of the maximum temperatures with respect to the vehicle surface and its corresponding internal structure. The CFD results for temperature, heat flux and surface pressure calculated for the selected critical flight condition show that the proposed concept for the instrumentation of both flaps and the capsule surfaces underneath the flaps is, generally in agreement with preliminary studies, but properties of TPS material on the flaps cavity flange should be enhanced to meet technical feasibility.