Author(s): Lai Wai Tan; Camilo Pinilla; Vincent H. Chu

Linked Author(s): Vincent H. Chu

Keywords: Dam-break waves; Open-channel flow; Simulations on dry bed; Lagrangian method; Finite-volume method; Flux limiting strategies; Courant stability criteria “The Lagrangian approach; Where the observer moves with the water

Abstract: Numerical simulations of the dam-break waves on a dry bed, and on wet beds, were conducted in order to show the inherent advantage of the Lagrangian Block Method (LBM) over the Eulerian method. The Lagrangian method always gives positive water depth. In contrast, the Eulerian simulation is affected by numerical oscillations. Stable solution by the Eulerian method is possible only if the waves are on artificial wet beds. Seven different flux limiters are employed to control the numerical oscillations encountered in the Eulerian simulations. The results of these Eulerian simulations for waves on artificial wet beds are compared with the results obtained by the LBM and with the analytical solution (see figures below). The Lagrangian method is not merely an alternative to the Eulerian method. Its ability to simulate waves on dry bed is unique, and should generally provide greater accuracy for flood wave simulations over dry bed.

DOI:

Year: 2007