Convergence acceleration using the residual shape technique when solving structure–acoustic coupling with the Patch Transfer Functions method

The forced response of the structure–water-filled cavity system is investigated from the Patch Transfer Functions method. In such a case, a poor convergence of the PTF method is observed when using standard mode expansion to build the cavity-PTF. To improve its convergence and maintain the advantages of substructuring, residual shapes are introduced in the cavity-PTF computation, which is the new material of this article. This technique is successfully applied on numerical examples, highlighting the interest of such an approach, especially in heavy fluid.