气泡群振荡及噪声数值模拟研究

针对水中气泡群振荡及辐射噪声问题，基于均质混合流模型，考虑气泡动力学作用，建立数学模型；并采用拉格朗日有限体积法，对气泡群振荡过程及辐射噪声进行数值模拟。重点研究了初始气泡半径、含气率及气泡群尺度等对振荡辐射噪声的影响。结果表明，随着初始含气率、气泡群尺度增大，气泡辐射噪声频率逐渐减小、声压幅值逐渐增大即声强增大；初始气泡半径对辐射噪声频率影响较小，但声压幅值随其增大而减小。

NUMERICAL RESEARCH ON THE NOISE IN THE OSCILLATION INSIDE A CLOUD OF BUBBLES

To learn more about the noise in the oscillation inside a cloud of bubbles,the nonlinear dynamics of a spherical cloud of bubbles have been simulated numerically with Lagrangian finite volume method. The simulations employ the fully nonlinear continuum bubbly mixture equations coupled with the Rayleigh-Plesset equation for the dynamics of bubbles. The impacts of initial bubble radius,void fraction and cloud radius on the noise are investigated by comparing the simulation results. The results show that the frequency of noise decreases with the increasing initial void fraction,cloud radius,and the noise intensity increases. The influence of initial bubble radius on the frequency of noise is minor,but the intensity decrease with it.