MAPPED INFINITE ELEMENTS FOR EXTERIOR WAVE PROBLEMS

Recently, new infinite elements which use r** minus **1 decay were proposed. They were applied to exterior wave problems and good results were obtained. In two-dimensional problems, however, it was necessary to move the origin of the r** minus **1 decay in order to model the outgoing wave more accurately, because it decays roughly as r** minus **1**/**2. In this paper, the mapped infinite elements with r** minus **1**/**2 decay and the necessary numerical integration procedure are presented. These elements do not require any artificial movement of the origin. Several example problems are solved. The results show that the infinite elements with r** minus **1**/**2 decay here give much more accurate values than the infinite elements with exponential decay and any damper elements.