Tests of Impact Acceleration on a Flat Bow Plate for a High Speed Craft

Abstract

Model tests of vertical impact acceleration of a planing boat bow flap at zero speed in calm water showed significant differences between a zero-angle and 12-degree angle of entry. The results differed from pressure measurements of impact found in the literature since the plates were flat and had no deadrise. However, the force proportionality with height, that is with v2, is confirmed. The structures can be represented by a single degree of freedom, with no consideration for trapped air, or water spray jets. Results indicate that the water provides a suction force, and preliminary theoretical calculations give a similar indication.