A Cartesian cut cell method for shallow water flows with moving boundaries

A new computational method for the calculation of shallow water hows with m oving physical boundaries is presented. The procedure can cope with shallow water problems having arbitrarily complex geometries and moving boundary e lements. Although the method provides a fully boundary-fitted capability, n o mesh generation is required in the conventional sense. Solid regions are simply cut out of a background Cartesian mesh with their boundaries represe nted by different types of cut cell. Moving boundaries are accommodated by up-dating the local cut cell information on a stationary background mesh as the boundaries move. No large scale re-meshing is required. For the flow c alculations, a multi-dimensional high resolution upwind finite volume schem e is used in conjunction with an efficient approximate Riemann solver at fl ow interfaces, and an exact Riemann solution for a moving piston at moving boundary elements. The method is validated for test problems that include a ship's hull moving at supercritical velocity and two hypothetical landslid e events where material plunges laterally into a quiescent shallow lake and a fiord. (C) 2001 Elsevier Science Ltd. All rights reserved.