Investigating the Effects of Cargo Weight and its Distribution on the Dynamic Performance of a High-Speed Planing Hull

Abstract

The aim of this article is to evaluate the effects of cargo relative weight and its distribution along the boat’s length in addition to the relative water wavelength on the dynamic performance of a high-speed planing hull. Here, the dynamic performance is measured by the intensity of the boat’s heave and pitch motions. The Zarnick’s strip theory, which divides the vessel’s hull into equal lateral sections, is used to study the applied forces on the vessel, and a MATLAB code is provided based on it. It is demonstrated that increasing the cargo weight and its distribution result in more heave and pitch, and the maximum amount of them are observed in the wave with a length of about 5 times the length of the boat. In addition, the interactive effects of cargo weight and its distribution on the heave and pitch motions are affected by the relative wavelength. Therefore, the more centralized cargo distribution is preferred to increase the dynamic performance of a heavy planing boat with cargo weights more than 50% of the boat’s weight, while moving in short waves (λ⁄L<4); and for light cargo weight, less than 50% of the boat’s weight, the favorite cargo distribution is broad. When the boat sails in long waves, the desired distribution is reversed.