Application of Smoothed Particle Hydrodynamics Model to Simulate Pier Scour in Laboratory Dam Break Flow

The progression of pier scour in flow was simulated using the public domain smoothed particle hydrodynamics (SPH) model called DualSPHysics (www.sphysics.org). First, the SPH model was verified by a dam break flow experiment on mobile bed channel with a pier installed. The simulated sediment particle velocity and bed surface profiles were compared with the measurements. Second, the SPH model was used as a numerical flume to study the evolution of pier scour in dam break flow. Results showed the maximum scour depth was reached quickly, but back-filled by sediment. Consequently, the end scour depth is smaller than the maximum scour depth. Besides, the available equations for calculating local scour depth yielded much larger results than the ones from the SPH model and laboratory measurements. This indicates the SPH model is capable of serving as a surrogate of laboratory flume for pier scour study.