Frequency-domain hybrid method on motions of ship with forward speed

Abstract

The paper presents a hybrid method in frequency domain to predict the wave induced motions on ships advancing in waves. A meshless cylinder surface in this solution is taken as the control surface by which the whole fluid domain is divided into the interior domain and exterior domain. The velocity potential and its normal derivative on the meshless cylindrical control surface are expanded into Laguerre-Fourier series. The forward speed Green function is adopted in the exterior domain. The Rankine Green function is used in the interior domain, and the cubic B spline technique is induced to compute the higher order derivatives of the velocity potential on the interior-domain free surface. The exterior domain and interior domain are connected by the continuous condition of fluid on the control surface. The excellent level of agreement with the known semi-analytical solutions and experimental measurements reveals that the present method is efficient and reliable to assess the seakeeping performance of ship with forward speed.