Computation of wave induced currents using "apparent" roughness concept

A method for determination of the "apparent" bed roughness using "k-l" turbulence closure model is developed. An approximate expression for apparent bed roughness calculations as function of wave and current parameters is derived. The domain of variable parameters is selected accordingly to the Israeli near-shore conditions. Flow patterns on the Tel-Aviv coast have been computed by employing the 3-D CAMERI flow model and by implementing apparent roughness maps, calculated by means of the approximate expression. Comparison of flow patterns computed with and without accounting for wave generated turbulence in the boundary layer shows that disregarding of the increase in bottom resistance in the 3-D model leads to essentially different results. Implementation of the apparent bed roughness maps to the 3-D model results in decrease of flow velocities and divergence of the velocity field around marine structures.