Three-dimensional non-hydrostatic model for dam-break flows

Abstract

A three-dimensional (3D) non-hydrostatic model is presented for the simulation of dam-break flows. The model solves the Reynolds-averaged Navier–Stokes equations using the projection method. 3D computational grids are constructed from a two-dimensional horizontal unstructured mesh by adding horizontal layers in the vertical direction. Based on the horizontal unstructured grid system, horizontal advection terms are discretized by a momentum conservative scheme. The proposed model is validated with several physical experiments. The agreement between the model results and experimental data is generally good, which demonstrates the capability of the proposed model to resolve dam-break flows over flat and uneven bottoms with complex geometries. Moreover, the efficiency of the model is evaluated with 3D dam-break flow experiments. Comparisons between the non-hydrostatic model and the corresponding quasi-3D shallow water model are also performed, which confirm the role of non-hydrostatic effects in dam-break flows.