Combined BEM and Perturbation to Analyze Wvae Refraction- diffraction

• Main Authors: Wu, Jen-Hong, 吳俊宏
• Other Authors: Hsiao Sung-Shan
• Format: Others
• Language: zh-TW
• Published: 1996
• Online Access: http://ndltd.ncl.edu.tw/handle/89384304913825961585

碩士 === 國立海洋大學 === 河海工程學系 === 84 === The study of the wave refraction-diffraction by boundaries such as island,bays and harbors are importance to ocean engineers. In the last years,various numerical models have proposed to mild-slpoe equation. Combinedboundary element method and perturbation and using dual reciprocity boundaryelement method have presented. The two numerical methods, one of them withdomain integral and the other with great matrix are complex. For improving the shortcomings this paper presents a new model. This paper presents a numerical model combined dual reciprocity boundaryelement method (DRBEM) and perturbation technique to analyze wave refraction-diffraction around a circular island on varying water depth. First, perturbation technique was used on the Mild-Slope equation, obtained a homogeneous Helmholtz equation and a nonhomogeneous Helmholtz equation. The homogeneous Helmholtz equation was solved by BEM, and the nonhomogeneousHelmholtz equation was solved by DRBEM. Comparisons are given with the analytical solutions and other numerical result. Good agreements are obtained.The model showed to be an adaptable method for solving wave refraction-diffraction problems.