Low frequency approximation of mutual modal radiation efficiency of a vibrating rectangular plate

This paper presents some elementary formulations for the mutual modal radiation efficiency
of a simply supported rectangular plate embedded into a rigid infinite baffle. The magnitude
makes it possible to introduce the intermodal plate’s interactions into the total radiation
efficiency of the plate vibrating under the influence of an external surface force. The
approximate formula has been expressed as a combinations of some trigonometric and special
functions. The formula is convenient for some numerical computations of the modal and total
radiation efficiency values of the plate.