AN EFFICIENT TOOL FOR MULTIFREQUENCY ANALYSIS IN ACOUSTIC SCATTERING OR RADIATION BY BOUNDARY-ELEMENT METHOD

In this article, a new boundary element algorithm in acoustic scatteri ng or radiation is proposed. Based upon a linear frequency interpolati on, this original method allows a real practical, fast and easy use of the boundary element method for a multi-frequency analysis. This tech nique is original for two reasons. The first one is the automation of its utilization using the interpolation between the two bounding frequ encies 0 Hz and the top-frequency of the spectrum given by the ''lambd a/4 criterion'' associated with the quadratic isoparametric discretiza tion for any geometry. Furthermore; in the case of its application to axisymmetrical problems, the circular surface elements of the mesh are automatically split through decomposition points. This allows a savin g of central processor unit time. Moreover, this profit increases very quickly with the size of the mesh and the number of calculation frequ encies. These motives make this boundary element linear interpolation method very attractive.