摘要 : A cooperative study for improving CFD as a design tool was carried out by three national organizations. The study was a part of a five-year research project “Intellectual Facilitation of Creative Activities” funded by the Science ... 展开 A cooperative study for improving CFD as a design tool was carried out by three national organizations. The study was a part of a five-year research project “Intellectual Facilitation of Creative Activities” funded by the Science and Technology Agency, and was included in the branch activity “Basic Study on the Support System for Creative Numerical Simulation”. In the branch activity the present authors carried out a study titled “Support of Creativity by the Merging of Numerical Simulations and CAD”, and the present paper reports the results. Hull forms were represented using NURBS. The hull form modifications for optimization were represented by overlapping a B-spline net onto the original NURBS net. This overlapping system was used to modify length and thickness of bow bulbs, and stern frame lines from U-shape to V-shape. As a hull form modification system suitable to hull form optimization, the y-coordinate overlapping spline system was developed to represent hull form modification with a minimum number of parameters. The implicit Geometrical Method (IGM), a grid generation method developed by one of the authors, was extended to multi-block hull surface grids to represent bulbous bows and stern overhangs. It was shown that the smoothing algorithm of the IGM is a discretized form of cubic spline functions. A series of CFD computations for tanker forms were carried out by systematically changing stern hull forms from V-shape to U-shape, and clarified the effect of the hull forms on the resistance, hull surface pressure distributions, and wake distributions. As an example of the optimization using CFD, a two-dimensional wing section was optimized to minimized drag while keeping the volume constant, and 12% drag reduction was obtained at the Reynolds number of R{sub}e=1.0×10{sup}6. 收起