This paper is an attempt to develop a method for determining the slamming pressures and loads on ship hulls, when the relative vertical velocity relationship between the wave slope and keel is specified. A basic two-dimensional theory for hydrodynamic impact is utilized which avoids linearization of the free surface. The mathematical model for the theoretical development is a wedge. A method of analysis is presented which yields the free surface shape and pressures associated with symmetrical penetration of a fluid surface by wedges of varying deadrise angle. The analysis is based on the principles of continuity of fluid flow and similarity. The principle of continuity makes use of the fact that the volume of displaced water above the original water line. The principle of similarity accounts for the proportional expansion of the free surface with continued penetration of the body. The free surface (consisting of both wave and spray) is considered to be increasing in such a manner that the slope and velocity of the surface is determined by the position and penetration velocity of the impacting body. Once the correct free surface shape has been determined by a graphical iterative method, for any instant of time, the associated velocity potential and pressure can be determined numerically for various points on the body.

http://archive.org/details/theoreticalinves1094513268

Lieutenant, United States Navy