Prediction of the complete second order wave drift damping force for offshore structures

摘要

Wave drift damping on floating bodies performing slow motion in all the three horizontal modes surge, sway and yaw is considered. The coupled radiation-diffraction problem is formulated in a relative frame of reference and the 3×3 monochromatic wave drift damping matrix developed consistently to second order in the wave amplitude. The bodies may be of general shape, and the depth arbitrary. Explicit formulae suitable for numerical calculation are obtained and implemented into a low order panel program. We here apply the model to four different offshore structures, and the results show that the wave drift damping force has an important contribution to the mean second order wave force.