The Prediction of the Added Resistance for the Trimaran Ship with Different Side Hull Arrangements in Waves

In this paper, a second-order steady-state approach and a three-dimensional pulsating source distribution method are applied to derive the added resistance on a trimaran ship advancing in waves. The added resistance treated here is the secondorder steady-state hydrodynamic force, which can be expressed as products of the ship-motion responses, the radiation potential, diffraction potential, and the incidentwave potential, and all related velocity potentials are in three-dimensional form. The steady flow potential is also included in the motion response calculation to investigate its effect on the added resistance. In order to validate the prediction method, the experiments for measuring the added resistance of a trimaran model in head waves were also handled in a National Cheng Kung University (NCKU) towing tank, and the related data are adopted to compare with the theoretical results. The comparisons show that the prediction results obtained in the paper generally agree well with experimental data; the validity of the prediction method applied here can be regarded as acceptable, and the effect of the steady flow potential on the added resistance of the trimaran ship can be neglected.