相干声线跟踪理论中的周期界面迭代散射 仿真方法*

界面声反射模拟是室内复杂声学现象仿真的关键。针对传统声学仿真方法对于周期散射结构存在条件下声场仿真精度较低的问题，本文发展了一种基于迭代散射模型的室内相干声线跟踪法。此方法以经典的相干声线跟踪法为基础，将室内中常见的周期散射结构进行几何形状上的简化处理，然后依据周期散射定理给出声波在界面上的散射方向及能量，并将原始声线迭代分裂为相应的散射子声线，继续对其跟踪处理，此迭代散射模型对周期散射结构上的界面散射现象进行了准确的模拟。数值验证结果表明，本文方法可以有效地在低频段提高室内声场仿真精度，可为具有复杂散射现象的室内仿真提供新思路。

A coherent ray tracing method for room sound field simulation based on iterative scattering model

The prediction of acoustic reflection is a key factor to the complex indoor acoustic simulation. the classical methods usually cannot achieve high accuracy of the indoor sound field simulation in the condition of there being periodic scattering structures in the room. For this problem, an indoor coherent ray tracing method based on iterative scattering model is developed in this paper. Based on the classical coherent acoustic ray tracing method, this method simplifies the geometric shape of the periodic scattering structure commonly used in the room, and then gives the scattering direction and energy of the acoustic wave on the interface according to the periodic scattering theorem. Then, the original ray is iteratively scattered into several sub rays and these rays are continuously traced. Based on this model, the interface scattering phenomenon can be accurately simulated. The numerical verification shows that the proposed method can effectively improve the accuracy of indoor acoustic field simulation in low frequency band, which provides a new support for indoor simulation with complex scattering phenomenon.