关键词: 声学, 非协调元, 协调元, 声压, 平均

Abstract: To solve the problem of corner point in surface in BEM, discontinuous element is employed for the discretization of Helmholtz boundary integral equation. The polar coordinate transformation in discontinuous element is presented so as to eliminate the singularity in the integration. Meanwhile, the CHIEF method and the Lagrange multiplier are applied to deal with the non-unique solutions. The value of acoustic pressures at the nodes can be acquired by solving a set of linear algebraic equations, acoustic pressure in grid points are obtained by taking the node average values or element average values. In order to demonstrate the robustness and accuracy of the proposed method, two numerical examples of sound radiation from a pulsating sphere and a cube are presented. The results calculated by discontinuous element are compared with the results determined by continuous element. The results have verified the efficiency and adaptability of the proposed method.

Key words: acoustics, discontinuous element, continuous element, acoustic pressure, average