基于大涡模拟的方柱绕流噪声特性研究

Large eddy simulation and Ffowcs Williams-Hawkings (FW-H) equation were used to investigate the aeroacoustic noise characteristics of flow around a square column. After verifying the accuracy of the numerical model, the influences of flow velocity and flow direction on noise field characteristics are discussed. The noise prediction result of the base model was in good agreement with the experiment data in the vortex-shedding frequency and in the general trend. It was shown that there were typical dipole noise sources in the direction of 110° and 250°, respectively. With the increase of distance, the total sound pressure level was decreased and the directionality of the noise field is becoming worse. The results showed that the vortex-shedding frequency was increased with the increase of flow velocity, and the corresponding sound pressure level was also raised. The change of flow direction would make the directionality of noise flied more complicated, which is related to the complexity of flow field.