Moving velocities of precursor soliton generation in two-layer flow

Based on the AfKdV equation, the theory on the velocities of the precursor soliton generation in two-layer flow over topography was presented. The moving velocities for precursor solitons, first zero-crossing of the tailing wave-train and flow behind the topography were found theoretically. It has been shown that for the given topography, when moving velocities are at the resonant points, the ratio of the moving velocity of the precursor solitons to that of the first zero-crossing of the tailing wave-train equals -4/3, and the ratio of width of generating region of the precursor solitons to that of the depressed water region equals also -4/3. The comparison between the theoretical and numerical results is found in good agreement.