Hull Form Optimization for Reduced Resistance and Improved Seakeeping via Practical Designed-Oriented CFD Tools

摘要

A practical designed-oriented computational tool has been further developed for the hull form optimization for reduced resistance and improved seakeeping. The main focus of this study is on the development of an efficient and effective hull surface modification techniques. Two approaches are utilized. One of them is based on the sectional area curve of the hull, and the other the radial basis function interpolation. These two approaches are combined to allow for both local and global modifications of hull forms. In order to optimize hull form for resistance and seakeeping, a multi-objective genetic algorithm is adopted. A practical design-oriented CFD tool and Bales' seakeeping ranking method are used for the evaluation of the objective functions associated with the resistance and seakeeping, respectively, and the hull form modification technique developed in this study is used to vary the hull forms during the optimization process. For the purpose of illustration, a surface combatant ship, the DTMB Model 5415, is taken as an initial hull, and the present multi-objective hy-drodynamic optimization tool is used to determine optimal hull forms for reduced drag and improved seakeeping at given design speeds. Numerical results obtained in this study have shown that the present computational tool can be used to develop hull forms exhibiting low resistance and superior seakeeping.