Effect of bow and stern shapes on the resistance characteristics of a catamaran

Now-a-days, a large number of marine vehicles are being developed to meet the increased demand for inland and coastal transporation services. Among these marine vehicles, the catamaran type is very popular due to its large deck area, adequate stability, good resistance and sea-keeping qualities. Since the propulsive power of any marine vehicle mainly depends on its resistance characteristics, it is essential to develop a suitable hull form of the marine vehicle in order to obtain better resistance characteristics which contemplate primarily on fuel economy. In the initial design stage, the propulsive power is usually predicted analytically by any one of the existing power prediction methods. But, however, it is necessary to conduct model tests to obtain the final hull form. Hence, for the present study, a 1:12 scale catamaran model was fabricated with change in bow and stern shapes and tested for three hull spacings in the towing tank at Department of Ocean Engineering, Indian institute of technology Madras, Chennai-600 036, India. The model test results are analyzed and presented with discussions in this paper.