Study on Porous Wave Makers

Abstract

A vertical porous wave maker sitting in an infinitely long channel of constant depth is studied. The wave maker performs horizontal oscillatory motion. A simplified analytical approach for thin porous wave maker and an approach of boundary integral method valid for a porous‐wave maker of any thickness are presented in this study. The fundamental assumption for an analytical approach of a thin porous wave maker is that the vertical velocity profiles are identical throughout the porous wave maker. The validity of the assumption for the thin porous‐wave‐maker approach is verified by the numerical solution of the boundary integral method. However, the numerical solution also shows very different results between thin and thick porous wave makers. The effect of inertial reactance on a porous medium compared with viscous resistance is also discussed in this study. When the flow‐efficiency parameter R defined in this study is greater than or equal to O(1), the inertial reactance can no longer be ignored as previous investigations did.