高超声速进气道再入流场特性研究

Research on Reentry Flow Field of Hypersonic Inlet

为揭示超额定工作状态下高超声速进气道的流场特性,针对设计点为飞行高度H=25 km,飞行马赫数Ma=5的二元三波系混压式进气道进行再入流场的数值模拟研究。研究发现:随着再入马赫数增大,两道斜激波不能在唇口处交汇,唇罩内表面分离增大,隔离段上表面的附面层变厚,进气道的总压恢复系数降低。为拓宽进气道在超额定状态下的工作范围,在进气道唇口位置开槽,开槽位置与唇口的距离越远,隔离段下表面的分离包越小;随着槽宽的增大,隔离段上表面附面层厚度先减小后增大,槽宽为2 mm时,附面层厚度减小约71.6%,效果最佳。

A series of numerical simulations were performed to investigate the flow field characteristics of a binary three-wave system hypersonic inlet port under over-rated operating conditions,with a design point of H=25 km and Ma=5.It is found that with the increase of Mach number,the two oblique shock waves cannot be located at the mouth of the lip.Increasing Mach number is helpful for separating the inner surface of the lip mask and thickening the surface layer on the upper surface of the isolation section.It also results in a reduction of total pressure recovery coefficient.In order to expand the working range at the over-rated design mach number,cowl bleed slot was designed.It is found that the farther the slot position is from the lip,the smaller the separation package is on the lower surface of the isolation section.As the groove width increases,the boundary layer thickness on the upper surface of the isolation section decreases first and then increases.When the bleed width is 2mm,the thickness of the boundary layer is reduced by about 71.6%,and the effect obtained the best.