气动噪声预测的关键在于提高流场的预测精度,特别是对涡流扰动的细节描述.文章采用的是计算流体力学(CFD)与“声比拟”相结合的方法,通过2个步骤模拟流动的声学远场.第1步,在包含所有声源的近场区域内,通过使用DES方法获得控制面处的非定常流场参数；第2步,采用基于可穿透数据面的FW-H方法模拟声学远场.该方法与传统的半经验方法相比,具有计算量小,计算精确,易于工程实现,可以计算非线性噪声.文中对比了URANS和DES 2种方法所算的气动噪声结果.在频域上计算了观测点处的声压级随斯托劳哈数和频率的变化,其结果与国外试验结果对比取得了较好的一致性.%Improving the accuracy of the flow prediction, especially the detailed description of the vortex disturbance , is the key of aerodynamic noise prediction. This paper uses acoustic analogy in combination with computational fluid dynamics. Sections 1 through 3 of the full paper explain our simulation approach mentioned in the title, which we believe is effective; their core consists of; (1) In the first step, the unsteady flow field is computed in a near-field domain comprising all acoustic sources via a DES solver; (2) In the second step, the FW-H integration approach with a permeable data surface is used to extend the dynamic near field to the acoustic far field; (3 ) compared with the traditional semi-empirical method, this approach requires less calculations but get results with better precision; most importantly, it can compute nonlinear noise and is easy to use. Section 4 gives simulation results for both near field and far field; it gives calculated results for both URANS and DES; it calculates respectively sound pressure level variations with frequency and Strouhal number; the results, presented in Figs. 9 through 14, and their analysis show preliminarily that our simulation approach is indeed effective.
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