A study into the effect of loading conditions on the resistance of asymmetric high-speed catamaran based on experimental tests

Abstract

Preparing high speed and sea keeping simultaneously are outstanding features of Catamaran boats (as one of multi-hull boats). In this paper, influence of loading conditions on drag through 6 series of experimental tests has been investigated. Experiments have been executed in a towing tank for model in scale 1 ratio to 11.43. Ultimately, results have been presented to full scale boat by Froude number and ITTC model. Loading conditions consist primarily of both weight of boat and longitudinal central gravity (LCG). Hence, adopted Catamaran has been examined in various loading conditions (light, full and over load) and two LCGs allocated to each weight in order to clarify effect of ones on drag. According to results whatever central gravity comes close to transom (backward position of LCGs), drag diminishes in high speed but increase in boat weight leads to decrease in its impact. As a consequence, the most descent of drag about 9.6% occurred in light load and maximum speed. Keywords: Catamaran, Load conditions, Towing tank, Drag