Computations of eigenfunctions and eigenfrequencies of two dimensional vibrating structures by the boundary element method

The determination of shapes and frequencies of eigenmodes is important in the analysis and design of distributed parameter vibrating control systems. This work is usually carried out by the Galerkin finite element method. However, when the medium is homogeneous, with damping distributed only on the boundary, the boundary element method is more convenient to use and readily gives excellent numerical solutions. The boundary element method and algorithms for computing the eigensolutions of the wave equation with viscous boundary damping are introduced. Eigenmodes are illustrated by computer graphics so that the reader can compare the changes of shapes effected by boundary damping parameters