EXPERIMENTAL AND COMPUTATIONAL STUDY OF CHANNELIZED WATER-WAVES GENERATED BY A POROUS BODY

We report about experiments on large amplitude shallow water waves tha t were generated by the sudden forward motion of a porous wedge-type p iston. The experiments are compared with those done previously [7] whe n the motion of a body with impervious boundary was examined. Close ag reement is obtained between the two sets of experiments if the porous body is sealed at its rear side, but differences are substantial witho ut the seal. The theoretical model is based upon the shallow water ass umption and an unsteady non-Darcy flow in an isotropic porous medium. The transfer of momentum from the porous body to the interstitial flui d is effected by a Darcy-Forchheimer type interaction, thus introducin g two free parameters which must be determined through matching with e xperiments. A finite difference scheme with flux corrected transport i s used to integrate these equations. Numerical results agree favorably with those from observations.