Wave transformations over porous beds

This study investigates wave transformation when wave pass over a submerged porous obstacle. The numerical model is based on the Boussinesq equation demonstrated by Cruz et al. (1997), and is expressed by depth-averaged velocity and depth-averaged seepage velocity. This model which introduces a parameter related to shoaling and seabed contours proposed by Madsen and Sorensen (1991), is applied to a larger relative water depth, h/L. The numerical model utilizes the Fourth-Order Adams-Bashforth-Moulton Predictor-Corrector Scheme and is coupled with a source function and absorbing boundary condition to enhance the stability of calculations and to reduce the required processing time. Numerical experiments are made to simulate the wave transformations over a submerged porous obstacle. Based on the numerical results, the effects of the transformation influenced by the porosities and the intrinsic permeability, k(p) are examined. The deformation of the primary wave and second harmonic wave indicates that the wave height decreases as the relative depth increases when the condition of the porosity is less than 0.44 and k(p)=2.5x10(-8) m(2).