Optimization of modular raft WEC-type attachment to VLFS and module connections for maximum reduction in hydroelastic response and wave energy production

摘要

This paper presents optimization of modular raft WEC-type attachment to VLFS and connections between floating modules of the VLFS for regular and irregular waves. The modular raft WEC-type attachment consists of multiple independent auxiliary pontoons connected to the fore edge of the VLFS with hinges and linear Power Take-Off (PTO) systems. The two objectives of the optimization are to maximize the reduction in hydroelastic response of VLFS and the power capture factor. The optimization process is proposed by using differential evolution (DE) algorithm. A numerical analysis framework based on finite element-boundary element (FE-BE) method is presented for determining the power capture factor as well as the hydroelastic response reduction for regular and irregular waves. The proposed optimization process is used to investigate the effects of the design variables, including PTO damping coefficient, pontoon length, the number of connections and connection stiffness, on the trade-off curve (i.e. Pareto front). In addition, the maximum power capture factor and hydro elastic response reduction are examined for various regular and irregular waves.