Numerical modeling of six-degree-freedom ship motion

摘要

The present invention's new calculative methodology models the motion of a seagoing vessel in six dimensions, uniquely employing a total velocity potential as the sole parameterization for taking into consideration all linear and nonlinear dynamical effects involved in interaction between the vessel and environmental water. The solid-body rotational motion of the vessel about the vessel's center of mass is determined in three dimensions (roll, pitch, yaw) by calculating the pressure torque and the buoyancy torque. The solid-body translational motion of the vessel's center of mass is determined in three dimensions (heave, surge, sway) by calculating the pressure force and the buoyancy force. The pressure torque and the pressure force are each associated with pressure (e.g., non-hydrostatic pressure) of water on the vessel's surface. The buoyancy torque and the buoyancy force are each associated with the displacement of the vessel with respect to the vessel's equilibrium position in the water.