基于声扰动方程的气动噪声传播积分计算方法  

Integral Computation Method of Aerodynamic Noise Propagation Based on the Acoustic Perturbation Equations

作　　者：郑雯斯 王芳[2] Zheng Wensi;Wang Fang(Northwestern Polytechnical University,Xi’an 710072,China;North Minzu University,Yinchuan 750030,China)

机构地区：[1]西北工业大学,陕西西安710072 [2]北方民族大学,宁夏银川750030

出　　处：《航空科学技术》2023年第12期30-36,共7页Aeronautical Science & Technology

基　　金：航空科学基金(201914053001)。

摘　　要：传统声比拟思想假设声传播介质均匀,所获得的远场噪声积分方法无法考虑近场流动非均匀性引起的声折射效应,声场预测结果往往存在较大的数值误差。为解决上述问题,本文采用声扰动方程描述声波运动,并利用声学互易原理,在频域内构建关联近场声源与远场声压的伴随格林函数,从而将非均匀介质折射效应纳入伴随格林函数。基于伴随格林函数和声扰动方程源项的数值结果,利用积分方程计算气动噪声的空间传播。结合上述方法对二维圆柱和NACA0012翼型绕流噪声开展了数值预测研究,远场声压预测结果与CFD直接计算值吻合。数值研究表明,本文提出的基于声扰动方程的气动噪声传播积分计算方法可以考虑非均匀介质对声传播的影响,能够提高气动噪声的预测精度。The integration method of far-field sound propagation based on the traditional acoustic analogy theory assumes that the acoustic medium is uniform,and it is difficult to account for the sound refraction in non-uniform media which causes large numerical errors in the prediction of noise field.In this paper,the acoustic perturbation equation is used to describe the sound wave motion,and the adjoint Green’s function is constructed in the frequency domain to relate the near-field sound source and the far-field sound pressure based on the acoustic reciprocity principle,so that the refraction effect of the inhomogeneous media is included in the adjoint Green’s function.By combining the numerical results of the adjoint Green’s function and the source terms of the acoustic perturbation equations,the spatial propagation of aerodynamic noise is calculated by the integration method.Combined with the above method,numerical prediction research is carried out for the noise induced by flow around the two-dimensional cylinder and NACA0012 airfoil,and the far-field sound pressure prediction results are in good agreement with that directly obtained by CFD.The integral calculation method of aerodynamic noise propagation based on the acoustic disturbance equation takes into account the influence of non-uniform media on sound propagation,which can improve the prediction accuracy of aerodynamic noise.

关 键 词：声扰动方程 伴随格林函数 气动噪声 声折射 

分 类 号：V211.3[航空宇航科学与技术—航空宇航推进理论与工程]