Abstract
Many of the studies of the interaction factors for arrays of wave energy devices concern systems in which the mechanical damping matrix (R) is specified as exactly equal to the radiation damping matrix (B). Although this represents an ‘optimal’ system of oscillating bodies, the damping and mass conditions required are difficult to engineer. Specifically, for the power generated by an array of bodies that each oscillate in a single mode, the mechanical damping matrix does not replicate the radiation damping which couples adjacent bodies, (R is diagonal whereas B is a dense matrix). Here, analysis is conducted using a frequency domain model based on hydrodynamic coefficients obtained from multi-body WAMIT analysis. We consider a five element array of hemispherical bodies in both terminator (beam-seas) and attenuator (head-seas) configurations in which power is generated from heave of each float only. Mass and mechanical damping are identified for each float to (a) maximize net power from the array and (b) minimize variation of average power across the array. We show that, by selecting appropriate values of damping for each float within the array, power capture can exceed that from an array in which damping is equal to the diagonal of either the radiation damping matrix or of the optimal damping matrix for a constant mass array.