Experimental research for the influence of stern towing force on a planing hull in the towed system

Abstract

New types of high-speed and near surface towing technology are getting attentions, and the prospect of adopting a high-speed small craft as the towing ship for towed system has been studied recently. The paper aims to investigate the effect of the towed cable on the dynamic behavior of the high-speed towing planing hull. In order to gain a better understanding of the effect of the stern towing force induced by the drag cable on the hydrodynamic performance of the planing hull, especially in the condition that the volume-Froude number is not larger than 3.0, the resistance, attitude and motion of a planing hull with and without towing force is investigated by model test in the condition of calm water and regular waves of different wave heights, and the effect of stern towing force is analyzed. The flow phenomena around the hull in calm water and the accelerations of the hull in regular waves are studied. It is found in the model test that, the planing hull's resistance could be reduced by the stern towing force around the velocity condition at which the volume-Froude number is close to 3.0. The motion of the planing hull is not obviously influenced by the towing force, but the accelerations are susceptible to the towing force.