Parabolization and structural integrity of side bulb applied to a platform supply vessel

Abstract

The waterline parabolization is a hull form-optimization method, Calisal et al. (2002) reported a 10% decrease in the effective horse power at Fr = 0.275 for a coaster tanker. The present study was made for an oil platform supply vessel (PSV) to improve the hull form, including structural work, and a cost, benefit analysis. The parabolization increased the vessel's beam by 5% and hull displacement accordingly. The required structural scantlings were calculated for the new parabolized hull, using the rules of American Bureau of Shipping (ABS). The study of a cost and payback analysis of the parabolized PSV showed, a net fuel savings of 280,000 liters/year, and provides US$235,000.00 per year saving, based on a 5.88% drop in resistance for an operation scenario. The payback period for the bulb is estimated to be nine to seventeen months. In addition, resistance reduction saves 753,900 kg of CO2 and 134,100 kg of NOx.