Alternative Wave-Induced Force and Moment Expressions for a Fixed, Vertical, Truncated, Circular Cylinder in Waters of Finite Depth

摘要

Two user-friendly expressions for the horizontal and vertical wave-induced forces on fixed, truncated circular cylinders are presented. The approximation of the horizontal force is that of van Oortmerssen, and that of the vertical force is based on a solution of the Laplace equation with a matching radial-force condition at the internal-external interface. The velocity potential resulting from the solution is assumed to be finite at the origin of the radial coordinate. Results obtained from both approximations are compared with results obtained from the rigorous analysis of Garrett. Also, results from the Froude-Krylov approximation for the vertical force are presented for the sake of comparison. The van Oortmerssen are shown to coalesce with the Garrett results for ka > 1.5, while the vertical force results compare well over the ka range studied.