A front-capture scheme for the simulation of homogeneous and particle-laden gravity currents

This paper presents a new finite volume scheme to efficiently simulate grav ity currents flowing over complex surfaces. The two-dimensional shallow-wat er equations, with terms to account for friction and particle transport, ar e solved using a non-oscillatory technique. By applying a form drag at the front or head of the dense current, the scheme also implicitly captures the correct Froude number condition at the moving front as it intrudes into th e less dense ambient fluid. The Froude number of the head region predicted by the numerical simulation is in good agreement with experimental results for a homogeneous current over a horizontal surface if a realistic profile drag coefficient is chosen. This new scheme avoids the development complexi ties of a general front-tracking scheme (e.g., handling merging fronts and multiple currents) and the computational cost of solving the full three-dim ensional Euler equations while providing a fast, accurate simulation of gra vity currents. Copyright (C) 2001 John Wiley & Sons, Ltd.