Modeling the Flow over Planing Hulls with Ventilated or Cavitating Steps

摘要

High-speed planing boats often employ stepped hulls to reduce frictional drag. The reduced drag is achieved through the formation of a vaporous cavity, which reduces the wetted surface area on the submerged hull. We are in the process of developing a numerical method to solve for the six-degree-of-freedom forces experienced by a cavitating, stepped planing hull. The approach will use a three-dimensional, time-domain potential-flow analysis embodied in the established code, Aegir. Aegir is a high-order boundary element method in which the source and dipole distributions on the boundary are represented by B-splines. Results of a two-dimensional implementation are presented in this paper, in which we examine the accuracy of a linearized solution. New model testing is underway in order to provide detailed validation for the proposed method.