FORCE MEASUREMENT COMPARISON OF BLUNT CONES IN HIGH-ENTHALPY SHOCK TUNNEL HEG AND HIEST

Abstract

Comparative aerodynamic test campaigns with the same test model are performing in the free-piston shock tunnel DLR-HEG and JAXA-HIEST under identical test flow condition. A blunted nose cone, which nose radius is 50mm, is adopted as the reference test model for direct comparison of both shock tunnels. In the previous aerodynamic test campaign of a blunt nose cone at JAXA’s HIEST shock tunnel, remarkable differences in the axial force coefficient between measurement and a numerical prediction were found. The first objective of the present study aims to investigate whether the discrepancy can be caused by poor testing accuracy or by the high-temperature real-gas effects. The second objective is uncertainty analysis of the employed two different force measurement techniques. The first one is optical tracking technique will be adopted in DLR-HEG, in which technique model movement is recorded with the high-speed video camera. The second one is the free-flight technique adopted in JAXA-HIEST, which technique uses accelerometers and miniature data recorders onboard in the model. In the script, the results measured with the free-flight technique in JAXA-HIEST was mainly described. Shock tunnel test campaign planned in near future in DLR-HEG will be also reported.