Efficient calculation of deformation and FEM stress for substructures of floating wind turbines

Abstract Design tools for floating wind turbines must be able to quantify the effects of elastic substructure flexibility. The implementation in HAWC2 is here validated against a physical model test with a generic floater. Next, the detailed stresses in the substructure require Finite Element Modelling (FEM). When the deformations are small, linear analysis is sufficient and superposition can be utilized. Thus following modest pre-computation, stress time series for any random realization can be achieved efficiently through influence functions and FFT based transfer functions. We present a proof of concept here.