Effects of continuum breakdown on aerodynamics of near space vehicle

Hypersonic vehicle suffer rarefied gas effect flying in near space. Attempt has been made to analyse aerodynamics of hypersonic vehicle near space with slip NS methods. The applicability of several different slip boundary conditions has been investigated. The difference between continuum and rarefied predictions for surface properties has been shown. The results show that present results are consistent to reference′s results. Pressure coefficient on the surface is affected by rarefied gas effect slightly, while heat transfer rate is most influenced by that. At Kn=0.25, the surface properties predicted by slip models excepting for Gokcen model tended to be higher than those predicted by DSMC. Gokcen model can be used in an extensive range of Knudsen number compared with others. Peak transfer rate differences for tapered wing with different methods range from over 1.6% for 50km of altitude to almost 14.5% for 80km.