Numerical acoustic simulation of flow around circular cylinders based on Lattice Boltzmann method and Ffowcs Williams-Hawkings acoustic equation

摘要

Based on the GPU acceleration technique, Lattice Boltzmann method (LBM) and Ffowcs Williams-Hawkings (FW-H) acoustic equation are adopted to simulate the noise generated by flow around fixed and rotating circular cylinders when Reynolds number (Re) is 200. The results show that the sound pressure level has a peak in the vertical direction and it is higher than that in the streamwise direction. The maximum sound pressure level is significantly reduced when the cylinder rotates due to the suppression of vortex shedding compared to the case of a fixed cylinder. For tandem cylinders, the maximum sound pressure level in the vertical direction increases as the spacing ratio increases, and for parallel cylinders, it decreases as the spacing ratio increases. In addition, when using graphic processing unit (GPU), the computational efficiency is improved greatly and the speed-up reaches nearly 100.