Bottom effects on the tower base shear forces and bending moments of a shallow water offshore wind turbine.

In this paper the tower base shear forces and bending moments of a shallow water offshore wind turbine have been rigorously calculated by using a nonlinear simulation method taking into account the bottom effects. It has been found that nonlinearly simulated realistic waves with bottom effects should be used as inputs in the stochastic time domain simulation in order to design an un-conservative support structure for the offshore wind turbine. In order to further improve the simulation efficiency, a transformed linear simulation method has been utilized in this paper for generating equivalent waves as those obtained from the nonlinear simulation method. The accuracy and efficiency of the transformed linear simulation method have been convincingly substantiated through the subsequent calculation examples in this article. • The loads and responses of a wind turbine are rigorously calculated. • Nonlinearly simulated waves with bottom effects are used. • A transformed linear simulation method is utilized. • The transformed linear simulation method can offer more accurate predictions of the loads and responses. • The transformed linear simulation method has a higher efficiency in comparison to an existing method. [ABSTRACT FROM AUTHOR]