불규칙파 중 부가저항에 관한 모형실험 및 추정식 결과 비교 연구

Abstract

The application of the linear superposition method, involving the use of added resistance coefficient and irregular wave spectrum, has been generally used for predicting added resistance in irregular waves. Nevertheless, both model test results and computational fluid dynamics (CFD) simulations have suggested that the relationship between added resistance and the square of wave height was not exactly linear. In this study, added resistance in irregular waves was compared between model test and correction methods results. First of all, added resistance coefficient was compared in regular waves between model test and correction methods in frequency response. Added resistance coefficient had a difference between correction methods which were suggested in ITTC guideline. The effects of nonlinear wave height were also observed in model test results. That is added resistance coefficient was differently predicted to wave height. The accuracy of each correction method was different depending on the vessel type and wavelength ratio. Also added resistance in irregular waves were compared between linear superposition method and direct method. Model test results in irregular waves were utilized in direct method. This paper comprehensively suggests the limitations associated with accurate predict on added resistance coefficient and linear superposition methods in predicting added resistance in irregular waves. Moreover,