管内声场计算的一种新的差分方法

本文提出一种新的计算管内声传播的差分方法。它采用MacCormack时间分裂显式格式,直接求解声压和声学速度的基本方程组,通过合适处理声学边界条件,成功地计算了三维矩形管内声场。文中还给出了全部计算格点的差分格式和稳定性条件。这种差分方法的特点是内存少,计算比较稳定,程序简单,调试方便。特别适合于三维声场计算。

A NEW FINITE DIFFERENCE METHOD FOR COMPUTING SOUND FIELD IN LINED DUCTS

This paper presents a new finite difference method to calculate the problem of sound propagation in ducts.The macCormack time-split explicit scheme has been used to solve the basic equations for determining the acoustic pressure and velocities.The problems of sound propagation in 3-D rectangular ducts have been solved successfully by use of this scheme with making an approach to the acoustic boundary conditions.The finite difference schemes for full grid points and stability condition of the method are also given in the paper.This new method needs far less storage and is more stable.Moreover,it is easier to program and debug,and,especially,is suitable for computing 3-D sound field.