Ship Hull Form Optimization for Improved Resistance and Effective Power

This study is focused on modifying streamline an existing offshore supply vessel (OSP) hull form to an IMO standard one so as to obtain an improved ship hull form with low resistance and power and also with highly efficient energy-saving performance. Using an analytical method there was significant increase in the design variables during the process of hull form modification and this was validated when Maxsurf software was used to modify the hull form. The analytical method used to perform the modification of pacific wrestler using response amplitude operator (RAOs) from Maxsurf then MATLAB to consider the modified and initial resistance values gotten from Maxsurf motion analysis used as the input values in comparing the resistance and power as against the vessel forward speed at 180 Degree and 135 Degree. Main dimensions of the ship were used to generate various hull models and Autodesk inventor used to present the various vessel hull form in solid form. The optimization was to improve on the vessel hydrodynamic performance in calm water as to achieve good sea-keeping condition, comfortability, manoeuvrability, reduced fuel consumption at 0,5,10,15,20,23 and 25 knots on regular sea wave condition of 4m. The various NURBs design diagrams gotten were used to run a computer motion simulation on regular sea wave of 4 meters for the both hull forms to ascertain a more favourable resistance, stability and rang at various speed on transit. MATLAB coding was used to calculate for the required power for both vessel considering the resistance values gotten from the maxsurf motion analysis which shows that there was reasonable reduction in the modified resistance of about 40 to 45%, and also power of about 30 to 25% and hydrodynamic location RAOs of up to 8 to 2% results. Comparing the results of the parent hull form to the modified hull form at 0 to 25 knots of the ship speeds on various location of the sea state towards the different degree of movement of the ship which demonstrates the validity of the proposed modification design strategy after bulb was designed into the bow section of the ship hull given the ship a better forward buoyancy, 20 to 25% of fuel efficiency, and increased speed.