水下稳态涡流场声传播的数值模拟和实验研究

声波穿过涡流场时声传播特性会发生改变，可由此判断涡流场的存在及其特征参数。文章首先推导了二维稳态涡流场的射线微分方程组，实现了声波通过涡流场的声线轨迹模拟。然后开展水池超声传感器实验，采用现代计算流体力学(Computational Fluid Dynamics,CFD)仿真方法获取涡流场参数。最后将通过涡流场声信号的时延结果，与实验测量值进行对比分析。结果表明，对于涡核半径为30 mm，最大切向速度为1.2 m·s^-1的涡流场，数值模拟误差小于10%，验证了基于射线声学的水下稳态涡流场声传播数值模拟的有效性。

Numerical simulation and experimental study of sound propagation in underwater steady vortex field

When sound waves pass through vortex field, the propagation characteristics of sound waves are changed, and hereby, the existence and characteristic parameters of vortex field can be judged. In this paper, the ray differential equations of two-dimensional steady vortex field are derived, and the trajectory of sound wave passing through vortex field is simulated. Then, the ultrasonic sensor experiment in pool is conducted and the parameters of vortex field are obtained by modern CFD simulation method. Finally, the numerical simulation results of acoustic signal delay in vortex field are compared with the experimental measurement results, and it is shown that the numerical simulation error is less than 10% for the vortex field with a core radius of 30 mm and a maximum tangential velocity of 1.2 m·s^-1, which verifies the validity of numerical simulation of sound propagation in steady underwater vortex field based on ray acoustics.