Research On The Optimizing Hull Form Of Semi-planing Yacht

The rapid development of economy in China leads to a promising future of yachtmanufacturers. How to improve the resistance performance of the yacht has long being asignificant point of yacht navigability and always being a technological difficult factor forlocal manufacturers.Based on a62-foot luxury yacht as the research object, this paper discussed influentialfactors of resistance and improved the resistance performance through modify the type line.First of all,this paper focuses on methods which predicting resistance performance inhalf a sliding state condition. Professional CFD software named Gambit and FLUENT areused in preprocessing and numerical simulation. The RNGκ model and VOF model isused in solving RANS equations to simulate motions of yachts in static water under differentspeed. Resistance of different speed was calculated and compared with the results of SIT andregression formula method. Further studies are taken on the flow field and stress of thebottom of the yacht as well as drafting and navigation condition in different speed.Secondly, this paper discussed the influence of dead rise angle of hull bottom,longitudinal centre of gravity and angular line shape for yacht with determined principaldimensions. By shaping the type line to optimize the resistance performance of yachts andcompare the two through numerical simulations.Finally, this paper improved the half experience and half theory formula method SIT andusing MATLAB writing resistance calculation program to calculate the yacht model withlowest resistance.