Multiple cluster scattering with applications to wave energy park optimizations
Malin Göteman
Abstract
Theory and methods to compute the wave field and hydrodynamic interaction in arrays of fixed or floating structures have many applications, ranging from offshore platforms to wave energy parks. Analytical iterative and non-iterative multiple scattering theory, and extensions thereof, are often used for this purpose. However, the computational cost grows with the number of interacting bodies, and studies of large arrays of independently moving bodies often require assumptions in terms of layout periodicity, expansion in different length scales, or neglected degrees of freedom. In optimization studies of wave energy parks, many simulations are usually required, implying that the existing methods are too slow. The current paper extends analytical multiple scattering theory by dividing the floats in clusters, and computes the hydrodynamic interaction within clusters exactly, but iteratively between clusters. The method constitutes a bridge between the iterative and non-iterative multiple scattering methods, and enables a faster modelling of parks of many floating bodies, to a retained accuracy. The proposed method is validated with numerical and analytical methods with excellent agreement, to a drastically reduced computational cost.