稀薄气体效应对尖前缘气动热特性的影响研究

针对未来高超声速巡航飞行器尖化前缘、大升力面的构型特征,分别采用NS方法和DSMC方法,对高超飞行器局部部件的模化外形进行了努森数从0.01～0.5变化时气动特性的计算分析,对比了连续流方法与稀薄流方法所得结果的差异性,给出了稀薄效应对局部气动热特性影响的定量分析,旨在研究局部稀薄气体效应对气动热特性分布的影响规律。结果表明,努森数从0.04～0.5变化时,连续流方法和稀薄流方法所预测的峰值热流差距可达25%～40%,稀薄效应对热流的影响已达到不可忽视的地步。相对于热流而言,物面压力分布对稀薄效应的敏感性较弱,局部热流对这种局部稀薄效应非常敏感。NS方法所预测的结果普遍大于DSMC方法所得结果。

Effects of Continuum Breakdown on Aerothermodynamics

An attempt has been made to analyse aerodynamics near sharp leading edge at Kn numbers from 0.01 to 0.5 by using NS and DSMC methods respectively.The purpose of this study is to investigate the effects of continuum breakdown on hypersonic aerothermodynamics.The results show that peak transfer rate differences range from over 25% for Kn=0.04 to almost 40% for Kn=0.5.Pressure coefficient on the surface is little affected by rarefied gas effect,while heat transfer rate is most influenced by that.In all cases,the surface properties predicted by DSMC tended to be lower than those predicted by NS.