A Numerical Study of a Two-Dimensional Stepped Planing Surface

Abstract

In this paper the performance of a stepped planing hull is analyzed through numerical simulation of the fully nonlinear flow under a two-dimensional body. The height and location of the step are systematically varied to investigate the resulting free-surface elevation, pressure profile on the body, and fraction of the total lift that is developed on the downstream portion of the body. The results indicate that indeed a larger step height will generate a larger lift-to-frictional-drag ratio. This suggests that the largest step possible should be chosen, with the upper bound for this dimension being the height in which the flow no longer reattaches to the after-body. The results show that the lift-to-frictional-drag ratio varies very little with respect to the step location over the range studied in this work.