Abstract: As a typical meshless numerical method, Smoothed Particle Hydrodynamics (SPH) method has natural advantages in modeling free surface flows. However, this method is computationally heavy and time-consuming. Therefore, this paper proposes a SPH parallel algorithm based on particle decomposition. The algorithm distributes all particles to each process evenly for calculation, and the sending, receiving as well as broadcasting functions are called only once at each time step of communication, which is easy to implement and has good scalability.  This parallel algorithm is used to carry out the numerical simulations of 2D dam-break flow and 3D droplet impact onto a liquid film. The results show that this SPH parallel algorithm can significantly reduce the simulation time and is conducive to 3D large-scale computation. The maximum speedup can reach more than 30 when the number of particles is greater than one million.

Key words: smoothed particle hydrodynamics;free surface flow;parallel algorithm, particle decomposition;numerical simulation