Tailing wavetrain generation in precursor soliton generation in two-layer flow

A theory of tailing wavetrain generation for the precursor soliton generati on in two-layer flow is presented by using averaged KdV equations (AKdV), w hich are derived by the authors in terms of Whitham's method of averaging([ 1,2]). From the AKdV equations, group velocities of the tailing wavetrain g eneration are obtained by means of generating conditions of the tailing wav etrains, furthermore an analytical solution of the tailing wavetrain genera tion is found theoretically. A comparison between the theoretical and numer ical results is carried out in the present paper, which shows that the theo retical results are in good agreement with the numerical ones, obtained fro m the fKdV equation in two-layer flow with the depth of unity in the rest.