宽高比对二元高超声速进气道性能的影响

Effect of aspect ratio on 2-D hypersonic inlet performance

关键词:  高超声速进气道  宽高比  隔离段  反压特性  数值仿真

Key words:  Hypersonic inlet  Aspect ratio+  Isolator  Characteristics of back pressure  Numerical simulation

摘要:

对相同迎风面积、不同宽高比的二元高超声速进气道在设计马赫数6.0和非设计马赫数下的三维流场进行了数值模拟,研究了宽高比对进气道流场特征及性能参数的影响。结果表明,随着宽高比的增加,由于进气道长度和气流浸润面积的变化,内压段进口总压恢复系数、进气道流量系数和内部阻力系数逐渐降低;由于侧壁附近三维流动区域占整个流场的比例不同,当宽高比较小时,侧壁附近三维流动效应对进气道性能影响显著,进气道的总压恢复系数相对降低、增压比升高、温升比升高、出口马赫数降低,小宽高比进气道的低马赫数起动性能趋于恶化;设计马赫数下,宽高比的增加使二元高超声速进气道的反压承受能力降低。

Abstract:

CFD simulations were performed on four 2-D hypersonic inlets with different aspect ratios in constant area.Effects of aspect ratio were analyzed at designed Mach 6 and other Mach numbers with different back pressures.The investigation suggest that with the reducing of length and wetted area while rising of aspect ratio,total pressure recovery coefficient of external compress ramp,mass flow ratio and coefficient of internal drag decrease;Inlet with low aspect ratio,as the huge area of three-dimensional-flow near the side wall,performance of inlet is affected notable and the starting ability become worse;When the inlets work in peak back pressure with design Mach number,the pressure that the 2-D hypersonic inlets can endure would reduce with the rising of aspect ratios.