Nonlinear Roll Damping and Roll Motion Study of Asymmetric Catamaran With Variable Layouts

Abstract Because of the interference between the main hull and side hull, the layout of asymmetric catamaran has a great influence on the seakeeping performance. In order to assess the characteristics of roll damping and roll motion of this kind of ship, firstly, a numerical prediction method of roll damping is established by CFD with overlapping grids to simulate the roll decay curves at different transverse and longitudinal spacing and ship speed. The roll damping property is analyzed by energy method and flow field monitoring. Then, based on the correction of nonlinear roll damping, the roll motion response in waves is calculated by 3D potential method. Finally, model tests are carried out to verify the numerical methods. The change of transverse layout has a great influence on the roll damping and roll motion of the asymmetric catamaran, while the longitudinal layout has a little influence on the roll performance. The research results of this paper can provide some useful reference for the design of asymmetric catamaran.