3-D ACOUSTIC INFINITE ELEMENT BASED ON AN ELLIPSOIDAL MULTIPOLE EXPANSION

In an improvement over conventional finite element techniques, an ellipsoidal infinite element is used for the modeling of acoustic fields in exterior, fluid-filled domains surrounding a structure. This ellipsoidal infinite element is based on a multipole expansion that describes, to arbitrary accuracy, any scattered and/or radiated field exterior to an ellipsoid. Significantly, the respective eccentricities of the three elliptical cross sections of the ellipsoid can take values that are arbitrary and mutually independent. The ellipsoidal infinite element is readily incorporated in any structural or acoustic finite element code.