STRUCTURE OF MIXING LAYER IN HIGH ENTHALPY HYPERSONIC FLOWS

高超声速湍流混合问题不仅是高速气体动力学的基础研究课题，也是激波研究的重要应用领域。这项国际联合研究计划是在激波研究中心流体科学研究所和多伦多航空航天大学研究所的密切合作下进行了三年的。迄今取得的成果如下：(1)通过建立可以处理非结构网格系统中的三维Naves-Stokes方程的有限差分格式，得到了高超声速湍流混合的数学模型。(2)为了在上述数值格式中包含化学反应项，对高超声速湍流混合的基本过程进行了详细的研究。(3)结合对高超声速湍流混合基本过程的理解，对激波运动和激波后的流动进行了全…实验研究研究了紧凑型自由活塞激波风洞及其异型喷管的流动特性：压缩管中的皮顿运动；喷管FOW的启动过程；隔膜位置对喷管流动的影响；喷管流动的皮特压力分布；驾驶员气体污染。在此基础上，发现异型马赫数为6的喷管的工作区域非常有限，因此设计了锥形喷管作为替代。(5)得到了马赫数为6的喷管的滞止热为14 mA/kg。二次曝光全息干涉观测已成功地应用于圆柱绕流的观测。(6)这些结果是在Jean Sislian教授1995-1997财年期间和Jurgen Schumacher先生1997年6个月期间密切合作下获得的。(7)目前所获得的结果已提交国际知名期刊发表。较少

Topics on hypersonic turbulent mixing are not only basic research topics of high speed gas dynamics but also important applications of shock wave research. This international joint research program has been carried out for three years under close sollaborations between the Shock Wave Research Center Institute of fluid Science and the Institute of Aerospace Studies University Toronto.Results so far obtained are summarized as following :(1) A mathematical modelling of hypersonic turbulent mixing has been obtained by establishing a finite difference scheme which can handle three-dimentional Navies-Stokes equations in unstructured grid systems.(2) In order to include the chemical reaction terms in the above mentioned numerical scheme, detailed elementary processes of hedrogen-oxygen reactions has been investigated.(3) In conjunction with understanding of elementary processes of hypersonic turbulent mixsing, the motion of shock waves and flows behing them has been investigated experimentall … More y and numerically.(4) The characteristic of a compact free piston shock tunnel and its contoured nozzle flow has investigated : piton motion in compression tube ; starting process of nozzle fow ; effect of diaphragm location on the nozzle flows ; Pitt pressure profile of nozzle flow ; driver gas contamination. Based upon these results, it is found that the contoured Mach 6 nozzle has a very limited working region so that a conical nozzle is designed for its replacement.(5) The stagnation enthalpy of 14 MA/kg and nozzle flow Mach number of 6 has been obtained. Double exposure holographic interferometric observation has been successfully applied to the flow over a cylinder.(6) The results have been obtained under close collaboration during the stay of Professor Jean Sislian for total 8 months from the fiscal years 1995 to 1997 and also the stay of Mr.Jurgen Schumacher for 6 month in 1997.(7) The results so far obtained are submitted for the publication in international journals having high reputation. Less