强激波-附面层干扰下的气流动态畸变研究

THE INVESTIGATION OF DYNAMIC DISTORTIONS IN FLOWFIELD DOWNSTREAM OF STRONG SHOCK-BOUNDARY INTERACTION

关键词:  流场畸度  激波干扰  进气道  紊流度  频谱分析

Key words:  Flow distortion  Shock wave interaction  Inlet  Turbulence  Spectrum analysis

摘要:

本文在一定附面层条件下,着重研究典型的强激波与紊流附面层干扰区下游扩压器出口的气流动态畸变,文中讨论了激波强度、扩压器壁面形状(直壁和曲壁)对动态畸变的影响.讨论了紊流度分布中四个峰值与相同截面上的总压沿高度分布的相互关系.最后对紊流度沿高度分布中的若干典型站的总压信号作功率谱密度和概率密度函数分析

Abstract:

In the condition of certain boundary layer,the dynamic flow distortion in a two-dimensional convergent-divergent duct at the interaction of typical strong shock to turbulent boundary layer is emphatically investigated in this paper.It is found experimentally that four turbulenlence peaks exist along the height of duct downstream of the interaction region,as well as that each peak corresponds respectively to the inflexion point of the Pitot pressure profile. The effects of shock strength and the duct geometry on the dynamic flow distortions are also discu-ssed.The power spectral density (PSD) and probability density function (PDF) of Pitot pressure signals at the typical condition of the turbulence profile are analyzed in detail.It is noticed that the pattern of PDF of the Pitot pressure signals in vortex sheet at intersection of λ-shock is similar to that of sine wave in Gaussian noise