Parametrically excited hydrodynamic solitons in an annular trough

Based on analysis of the experimental data, a new equation governing the mo tion of solitons in a narrow annular trough is proposed using the multiple- scale method. Both analytical and numerical analyses reveal that the equati on gives a good explanation for some of the typical experimental observatio ns on the evolution of the single and double solitons as well as the effect of surface tension on the solitons. It also predicts some new kinds of mot ion of the solitons.