基于NLAS空腔噪声被动控制数值模拟

摘要

脉动压力（噪声）预测是飞行器内埋弹舱关键技术之一，非线性噪声求解方法是近年来新提出的一种噪声求解方法。为研究新方法对于空腔噪声的预测性能，选取长深比为5：1的空腔进行研究，计算了马赫数Ma＝0．85条件下的空腔噪声。 RANS计算采用Cubic k-ε模型用于求解空腔流场，计算得到当地雷诺应力张量和热通量的统计平均值，将其插值到噪声计算网格，根据这一统计平均结果对湍流进行人工重构。通过与试验结果对比，验证了方法预测空腔噪声的可靠性，研究了两种被动控制措施对于空腔噪声的抑制作用，结果表明，带RF和STS的腔体内部的压力幅值及总声压级都明显降低，且STS的抑制效果更好。%Prediction of oscillating pressure is a key technology for the weapon bay of aircraft cavity.Non-Linear Acoustics Solver ( NLAS) is proposed as a new method to analyze noise recently.In order to e-valuate the reliability,a length to depth radio of 5:1 at Mach 0.85 are investigated.Local Reynolds stress tensor and heat flux are obtained by calculating RANS equations on Cubic k-εmodel and then interpola-ted into acoustic mesh.Turbulence is reconstructed based on the statistic average result.Its reliability is checked by comparing with the test results.On this basis,NLAS method is applied into research on the in-hibition effect of passive control method for cavity noise.The results show that pressure amplitude and OASPL inside cavity with RF and STS are reduced significantly,and STS is better than RF.