开式方腔可压缩流动及噪声LES计算分析  

Large eddy simulation of compressible open-cavity flow and noise

作　　者：冯峰[1] 王强[1] FENG Feng;WANG Qiang(Aerodynamic Science Center, China Academy of Aerospace Aerodynamic, Beijing 100074, China)

机构地区：[1]中国航天空气动力技术研究院,空气动力科学中心,北京100074

出　　处：《兵器装备工程学报》2022年第1期170-175,211,共7页Journal of Ordnance Equipment Engineering

基　　金：装备预研领域基金项目(6140206040103)。

摘　　要：采用基于低色散、低耗散计算气动声学方法的LES技术计算分析了Mach 1.4和Mach 0.6三维开式方腔可压缩振荡流动及其诱导的强噪声环境。通过与已有实验和数值结果对比,证实了本文开发的LES计算程序的可靠性。深入分析LES空腔流计算结果,表明超声速来流条件下剪切层大尺度涡结构与空腔后缘撞击形成了声-流耦合自持振荡的声反馈环现象。同时,复杂非线性涡系运动导致超声速空腔流呈现出多个特征频率主导的压力脉动特性。当压缩效应减弱时,亚声速空腔流动的剪切层涡团与空腔后缘撞击形成与超声速情形基本一致的声-流共振现象,但压力脉动幅值显著减弱,且脉动频率减小。The large eddy simulation(LES)technique based on low dispersion and low dissipation computational aeroacoustics was used to analyze the compressible oscillating flow in Mach 1.4 and Mach 0.6 open-cavities and the strong noise environment induced by them.The reliability of LES code developed was verified by comparing the present results with the experimental and numerical results.The depth analysis of the LES cavity-flow results shows that the large-scale vortex structure in the shear layer collided with the trailing edge of the cavity under the condition of supersonic flow,formed an acoustic feedback loop of acoustic-fluid coupling self-sustaining oscillation.Meanwhile,the complex nonlinear vortical motion leads to the pressure fluctuation characteristics dominated by multiple characteristic frequencies.When the compression effect is weakened,the shear layer vortices collide with the trailing edge of the cavity to form an acoustic flow resonance under the condition of subsonic cavity flow,which is basically consistent with the supersonic case,but the amplitude and frequency of the pressure fluctuation are significantly reduced.

关 键 词：开式空腔 LES 声反馈 可压缩湍流 计算气动声学 

分 类 号：TJ8[兵器科学与技术—武器系统与运用工程] O35[理学—流体力学]