  Implementing particle-interaction configuration and time integration are
performance intensive essentials of particle-based methods. In this paper, a
dual-criteria time-stepping method is proposed to improve the computational
efficiency of the weakly-compressible smoothed particle hydrodynamic (WCSPH)
method for modeling incompressible flows. The key idea is to introduce an
advection time criterion, which is based on fluid velocity field, for
recreating the particle-interaction configuration. Within this time criterion,
several steps of pressure relaxation determined by the acoustic time criterion,
based on the artificial speed of sound, can be carried out without updating the
particle interaction configuration and much larger time-step sizes compared
with the conventional counterpart. The method has shown optimized computational
performance through CPU cost analysis. Good accuracy and performance is
obtained for the presented benchmarks implying promising potential of the
proposed method for incompressible flow and fluid-structure interaction
simulations.
