Author(s): Frank Liu; Ben R. Hodges

Linked Author(s): Ben R. Hodges

Keywords: Finite volume method; Hydraulic jumps; One-dimensional models; Open channel flow; Saint-Venant equations; Shallow flows; Streams and rivers

Abstract: A new finite-volume numerical method for the one-dimensional (1D) Saint-Venant equations for unsteady open-channel flow is developed and tested. The model uses a recently-developed conservative finite-volume formulation that is inherently well-balanced for natural channels. A new timescale interpolation approach provides transition between 1st-order upwind and 2nd-order central interpolation schemes for supercritical and subcritical flow, respectively. This interpolation meets a proposed “no-neighbour” criterion for simplicity in future parallel implementation. Tests with a highly-resolved transitional flow and a coarsely-resolved natural channel show that the method is stable and accurate when applied with a flowrate damping algorithm that limits propagation of energy down to subgrid scales.

DOI: https://doi.org/10.1080/00221686.2019.1671510

Year: 2020