Numerical and Experimental Studies on Diffraction of Water Waves Around Three-Cylinder Group

Abstract

The present study is concerned with numerical and experimental investigations on wave diffraction around bottom-fixed, surface-piercing, rigid, vertical, three-cylinder group of large diameter situated in constant water depth. The numerical analysis is based on the first order diffraction theory. Numerical solutions of the complex velocity potential and associated wave hydro-dynamic forces are obtained using two-dimensional finite elements in the inner domain in combination with infinite elements in the outer domain which directly satisfy the radiation condition. The assembly and solution of the finite element equations are based on the frontal scheme due to Irons (1). Extensive numerical results of wave forces have been obtained for the three cylinder group for various scattering parameters, wave angular approaches and spacing parameters. Experiments have been conducted on model cylinders to verify the validity of the numerical solutions. The present FEM results and experimental results have been compared with the other published analytical solutions. Due to the interference effect the increase in force on one cylinder due to the presence of the other cylinders is also presented.