Abstract: As a relatively new meshless particle method,smoothed particle hydrodynamics(SPH) method has an excellent advantage in dealing with largely-deformed free surface flows.The detailed numerical method about SPH is introduced in this paper,and two 2D dam break cases are simulated with SPH method.The numerical results are compared with experimental data,showing that: SPH method has a very good flexibility in tracking free surface.Though there are violent changes in free surface,such as turn up and breaking,SPH m...