Gu Xinzhong, Yao Jia
School of Automotive Engineering, Changshu Institute of Technology, Changshu 215500, China.
J Acoust Soc Am. 2021 Sep;150(3):1912. doi: 10.1121/10.0006111.
A computational method to predict the aeroacoustic sound produced by the interaction between fluid and moving body is developed, then applied to the problem of aerodynamic noise radiation from an engine cooling fan. The flow field is computed using the viscous vortex method with a simplified diffusion algorithm, followed by a noise sources extraction within the turbulent region, based on the vortex sound model. Then, the sound field is determined using a Convolution Quadrature Boundary Element Method, accounting for the scattering effect from solid surface. With the help of Convolution Quadrature Method, time-stepping Boundary Element procedure can be established circumventing the requisite for time-dependent fundamental solution. Fast Multipole Method is also adopted to improve computational efficiency. It is found that the results of flow field calculation are close to those obtained from measurement. The predicted noise levels at the microphone position are in qualitative agreement with the measured. The comparison of computation time also shows that the proposed method can effectively predict the fluid-blade interaction noise.
开发了一种计算方法，用于预测流体与运动物体相互作用产生的气动声学声音，然后将其应用于发动机冷却风扇的气动噪声辐射问题。使用具有简化扩散算法的粘性涡方法计算流场，然后基于涡声模型在湍流区域内提取噪声源。然后，使用卷积积分边界元法确定声场，该方法考虑了固体表面的散射效应。借助卷积积分法，可以建立时间步长边界元程序，从而避免了对与时间相关的基本解的需求。还采用快速多极子方法提高计算效率。结果表明，流场计算结果与测量结果接近。传声器位置处的预测噪声水平与测量值在定性上一致。计算时间的比较也表明，所提出的方法可以有效地预测流体-叶片相互作用噪声。
