采用五阶weighed esseritially non-oscillatory (WENO)格式和三阶total variation diminishing (TVD) Runge-Kutta格式,通过求解二维非定常Navier-Stokes方程,直接数值模拟了激波与剪切层相互作用,目的在于揭示激波与剪切层相互作用过程中噪声产生的机理.研究发现:(1)当入射激波穿过剪切层时,剪切层中心位置向下层区域偏移；(2)入射激波穿过剪切层产生小激波,在小激波与剪切层接触点处产生声波并向外辐射；(3)反射激波穿过剪切层后形成了分段弧状激波；(4)当反射激波穿过剪切层时,激波在鞍点处泄漏并向外辐射声波,这是一种激波泄漏机制.%Direct numerical simulation (DNS) of the interaction of shock wave and shear layer was performed. The compressible unsteady two-dimensional Navier-Stokes equations were solved using the fifth-order WENO scheme combined with the third-order TVD Runge-Kutta scheme. The purpose of this paper is to reveal the mechanism of sound generation in the interaction of shock wave and shear layer. The results show that: (1) When incident shock wave is passing through the shear layer, the center of the vortex cores is shifted towards the lower side; (2) The interaction of incident shock wave and shear layer generates shocklet, and then acoustic wave is generated and radiated at the locus of contact of shocklet and shear layer; (3) Several arc-shocks are formed after reflected shock wave passing through shear layer; (4) When reflected shock wave is passing through shear layer, shock wave is leaking in the braid region and shock-associated noise is generated at the saddle points between vortices. This is a form of shock leakage mechanism.
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