Optimization Of Ship Hull Resistance Based On CFD Method

Ship hull optimization which plays an important role in the overall design of the ship is a complicated and onerous design project. It is the key link of the research and application of the ship hydrodynamic theory, and it also has a significant impact for the technical and economic utility for the ship. If we can design a ship hull which has the minimum resistance which is an important index for ship hydrodynamic performance, it will save a lot of manual labor, material, time and expenditure. In recent years, along with the great development of ship Computation Fluid Dynamics, optimization of the ship hull based on hydrodynamic performance become a very valuable research direction.The Wigley hull is taken as an experimental hull type. Based on Rankine source method, SHIPFLOW is used as the computing tool, FRIENDSHIP-Framework is used as the integration platform of CAD-CFD, to study the minimum wave resistance design of the Wigley hull body, and the total resistance is investigated as well. The result shows that the wave resistance fits well with the experimental date, meaning that the computation method is reliable. Compared to the original hull type, the total resistance of the optimizated hull body which has the minimum wave making resistance is reduced, connoting that the method for the optimization is effective.3100TEU is also studied for the wave resistance computation and optimization. The optimized bulb shape matches well with the ones in the related research, so according to the result, it can be concluded that the bulb with a forward and upward extending would improve the wave making performance. Similar to the Wigley hull study, the total resistance of 3100TEU is also investigated, and the result shows that the total resistance is reduced as well.Based on Rankine source method, the wave resistance of some VLCC hull type is computed, and the total resistance is forecasted through empirical formula. SST k-ωturbulence model is taken to compute the viscous flow around the hull, whose result shows that the viscous separation around the bilge of the aftbody is very short which is easily leading to the generation of the vortex. Aimed to improve the viscous separation situation around the bilge of the aftbody of the VLCC, the affected region is transformed. The result shows that the change between the ones before and after the transformation is tiny. Although the result is not encourging, it can give us some guidance and reference.