流激噪声数值计算方法及声学积分面影响性研究

Research on numerical simulation approach for flow induced noise and the influence of the acoustic integral surface

在流声耦合领域中,水下航行体复杂流动与流激噪声研究具有重要的学术意义与实用价值。文章对FWH声学类比方法、渗流FW-H声学类比方法、Kirchhoff方法与Powell涡声理论进行了物理内涵与数学公式的详细比较;然后利用大涡模拟结合四种声计算方法数值计算了三维NACA0015机翼、机翼/圆柱结合体、方腔产生的流激辐射噪声,并与国内外试验结果进行了对比,分析了四种声计算方法的计算精度与计算效率;最后,对围壳流激噪声进行了数值预报与试验验证,计算了围壳在不同水速下的流激噪声变化规律,并探讨了声学积分面对计算结果的影响。

Study on the complicated flow field and flow induced noise of underwater vehicle has obvious theoretical meaning and practical significance in flow-acoustic coupling domain. In this paper, four pre-diction approaches for flow induced noise including FW-H acoustic analogy, porous FW-H acoustic analo-gy, Kirchhoff equation and Powell vortex sound theory are analyzed and compared with each other. The flow induced noise of three-dimensional NACA0015 airfoil, rod-airfoil and cavity are computed by LES with the four approaches. And, the numerical simulations are validated by the measurements. The accuracy and ef-ficiency of the four acoustic calculation approaches are studied. Finally, the flow induced noises of subma-rine sail at three velocities are predicted by the porous FW-H acoustic analogy and compared with experi-mental data. The tendency of sail flow induced noise under different velocities is analyzed and the influ-ence of acoustic integral surface is studied.