小尺度阻尼边界封闭空间声传递函数的有限元素法计算

Use of finite element method for computing sound transfer function in small enclosed-room with damped boundary

如何求解阻尼边界封闭空间中声源点到接收点的低频声传递函数已成为目前小尺度封闭空间可听化技术研究的关键技术。能处理任意形状及复杂边界条件的有限元素法可作为求解该问题的适合方法。以室内声场有源Helmholtz方程及其相应边界方程为基础,本文推导出了用于小尺度阻尼边界封闭空间声传递函数的有限元素求解方法,并编制了相应的计算机程序。在算例中,首先通过与模态叠加法计算结果进行比较,验证了该方法的正确性;最后计算了某型车体内腔中任意两点间声传递函数。

How to compute low frequency sound transfer function from source to re-ceiver in an enclosed room has become a key problem in small-enclosed room auralization. Due to its ability to process boundary conditions of arbitrary shape and complexity, fi-nite element method (FEM) may be used to solve this problem. In this paper, based on Helmholtz equation with sources and its boundary equations, equation for FEM is first given for computing sound transfer function in a small enclosed-room; secondly, com-puter program is written for a rectangular enclosed-space and the result of computing is compared with that given by the mode superposition method; finally, sound transfer function inside one kind of car is computed.