post-processing technique for removing ‘irregular frequencies’ and other issues in the results from BEM solvers

Within the wave energy community, hydrodynamic coefficients obtained from boundary element methods (BEMs) are commonly used to predict behaviour of converters (WECs) in response incident waves. A number commercially-available BEM solvers exist, with a open-source alternatives also available. While have an obvious cost advantage compared their commercial counterparts, results such often susceptible so-called ‘irregular frequencies’, which arise ill-conditioning integral problems, and result large under- or over-estimation parameters at certain excitation frequencies. Furthermore, while may employ techniques suppress effects irregular frequencies, may, under circumstances, exhibit other problems produced. For example, for added mass high infinite frequency water column, be incorrect. The current work first focusses on approach remove frequencies radiation damping particular WEC geometry. use obtain values mass, through Ogilvie relations, is then considered.The technique described herein has been implemented BEMRosetta, tool allows user view various solvers, as well converting input files between solvers. presented this paper using BEMRosetta implementation.