Damped waves generated by a moving pressure distribution

Free surface flows generated by a moving distribution of pressure are consi dered. The fluid consists of two superposed layers in a two-dimensional cha nnel. The upper layer is inviscid and the lower layer, which is introduced as a damping mechanism, is modelled by the mathematically convenient lubric ation equations. Numerical and analytical solutions are presented. Special attention is given to solutions for which there is a train of waves on each side of the distribution of pressure. It is shown that, depending on the v alues of the parameters, the short waves can appear on either side of the d istribution of pressure.