Smith Tom A, Chen Guanjiang, Zang Bin
Department of Mechanical Engineering, University College London, Gower Street, London, WC1E 6BT, United Kingdom.
Faculty of Engineering, University of Bristol, Bristol, BS8 1TR, United Kingdom.
J Acoust Soc Am. 2023 Sep 1;154(3):1585-1595. doi: 10.1121/10.0020912.
Bio-inspired geometries have many applications in engineering, including in the field of noise control. In this work, the aeroacoustic performance of a seal vibrissa shaped cylinder (SVSC) is investigated and compared to that of a circular cylinder at Re = 37 000. Experiments conducted in an anechoic wind tunnel are compared to results from a hybrid aeroacoustic simulation with excellent agreement observed between the two. The overall sound pressure level is found to be 24.3 dB lower for the SVSC, and no prominent narrowband component is observed in the acoustic spectrum. Analysis of the flow field and surface pressure fluctuations reveals that this is because the usual large-scale alternating vortex shedding realized for bluff body flows is absent for the SVSC. Instead, smaller uncorrelated vortices are shed from the upper and lower sides of the geometry, which, when combined with a lower spanwise correlation, results in a much lower acoustic intensity spread over a broader frequency range.
仿生几何形状在工程领域有许多应用，包括在噪声控制领域。在这项工作中，研究了海豹触须形状圆柱体（SVSC）的气动声学性能，并在雷诺数Re = 37000时将其与圆柱体的性能进行了比较。在消声风洞中进行的实验与混合气动声学模拟的结果进行了比较，两者之间观察到了极好的一致性。发现SVSC的总声压级低24.3dB，并且在声谱中未观察到突出的窄带成分。对流场和表面压力波动的分析表明，这是因为SVSC不存在钝体流动通常会出现的大规模交替涡旋脱落。相反，较小的不相关涡旋从几何形状的上侧和下侧脱落，这与较低的展向相关性相结合，导致在更宽的频率范围内声学强度低得多。
