Achieving Drag Reduction with Hullform Improvement in Different Optimizing Methods

Abstract

In general, evaluation of ship hydrodynamic efficiency could be produced by an energy-efficient and concentrated cost function. An optimization method with the representation of hull geometry is one of the preliminary design steps that are most appropriate for evaluating hydrodynamic performance. This work presents a comparison of two numerical methods for optimizing the shape of the hull concerning the minimization of total ship resistance in calm water conditions. The optimization method uses a theoretical approach based on Michell's integral and Rankine source methods. The discussion of the two methods emphasizes the comparison of wave resistance, total resistance, wave profiles, and wave contour. The optimized hull form comparison of total resistance between Michell's integral and Rankine source methods decreased by 3.79% and 4.0%, respectively. Comparing wave resistance with decreases by 5.52% based on Michell's integral method and 13.33% by the Rankine source method, the wave profiles generated by these two methods present a fair amount of compatibility. The wave contour illustrates a reasonably straightforward agreement on the optimal hull but are dissimilar on the initial hull.