Experimental investigation of waverier aerodynamic forces in supersonic and hypersonic slip regime
Résumé
This paper presents an experimental investigation focused on aerodynamic forces of a waverider in supersonic and hypersonic slip regime. This study is carried out in the laboratory ICARE of CNRS with the wind tunnel named MARHy. This facility recreates supersonic and hypersonic rarefied flows thanks to different nozzles and a pumping unit able to stabilise low free flow pressure inside the testing chamber for several hours. The waverider investigated is a hypersonic glide vehicle which is optimized for a Mach number 10 and an altitude range between 40-50 km. During this experiment the waverider will be investigate for diffferent flows which are far from the initial optimized conditions. The objective is to investigate how viscous effects can impact the aerodynamic of waverider when these vehicles are not optimized for these conditions. Four supersonic rarefied flow allowed to investigate the impact of the variation of Mach number and free flow pressure on the maximum of Lift-to-Drag ratio. This parameter need to be maximise during a flight to travel the highest distance possible. Increase of Mach number and free flow pressure improve aerodynamic performance for supersonic flows. A fifth nozzle is investigated, it is an hypersonic rarefied flow which reproduce an extreme condition where the Mach number is maximum at high altitude so high viscous effects. For the hypersonic nozzle, aerodynamic performances are low and the behave of lift curve is abnormal compare to theory. Finally, maximums of Lift-to-Drag (L/D) ratio are compared to Knudsen number to establish a general trend of the variation of maximum of L/D ratio in function of a rarefaction parameter.