Boundary element method for simulating the coupled motion of a fluid and a three-dimensional body

A boundary element method for potential flow problem coupled with the dynamics of rigid body was developed to determine numerically the resultant force and moment of force acting on an arbitrarily three-dimensional solid body and its motion in a current of an infinite fluid. An accurate integration method for singular integrands occurring in the boundary integral equations, a computational method for the tangential gradient of a velocity potential on a surface, and a method to properly treat the singularities appearing in the system of the dynamic equations of a rigid body, were proposed to complete the numerical solution of the problem. Several numerical examples were given to show the validity of the method.