Modelling dam-break flows over mobile beds using a 2D coupled approach

Xia, Junqiang, Lin, BinLiang ORCID: https://orcid.org/0000-0001-8622-5822, Falconer, Roger Alexander ORCID: https://orcid.org/0000-0001-5960-2864 and Wang, G. 2010. Modelling dam-break flows over mobile beds using a 2D coupled approach. Advances in Water Resources 33 (2) , pp. 171-183. 10.1016/j.advwatres.2009.11.004

Full text not available from this repository.

Abstract

Dam-break flows usually propagate along rivers and floodplains, where the processes of fluid flow, sediment transport and bed evolution are closely linked. However, the majority of existing two-dimensional (2D) models used to simulate dam-break flows are only applicable to fixed beds. Details are given in this paper of the development of a 2D morphodynamic model for predicting dam-break flows over mobile beds. In this model, the common 2D shallow water equations are modified, so that the effects of sediment concentrations and bed evolution on the flood wave propagation can be considered. These equations are used together with the non-equilibrium transport equations for graded sediments and the equation of bed evolution. The governing equations are solved using a matrix method, thus the hydrodynamic, sediment transport and morphological processes can be jointly solved. The model employs an unstructured finite volume algorithm, with an approximate Riemann solver, based on the Roe-MUSCL scheme. A predictor–corrector scheme is used in time stepping, leading to a second-order accurate solution in both time and space. In addition, the model considers the adjustment process of bed material composition during the morphological evolution process. The model was first verified against results from existing numerical models and laboratory experiments. It was then used to simulate dam-break flows over a fixed bed and a mobile bed to examine the differences in the predicted flood wave speed and depth. The effects of bed material size distributions on the flood flow and bed evolution were also investigated. The results indicate that there is a great difference between the dam-break flow predictions made over a fixed bed and a mobile bed. At the initial stage of a dam-break flow, the rate of bed evolution could be comparable to that of water depth change. Therefore, it is often necessary to employ the turbid water governing equations using a coupled approach for simulating dam-break flows.

Item Type:	Article
Date Type:	Publication
Status:	Published
Schools:	Advanced Research Computing @ Cardiff (ARCCA) Engineering
Subjects:	T Technology > TA Engineering (General). Civil engineering (General) T Technology > TC Hydraulic engineering. Ocean engineering
Uncontrolled Keywords:	Morphodynamic model; Dam-break flows; Mobile bed; Coupled solution; Finite volume method
Publisher:	Elsevier
ISSN:	0309-1708
Last Modified:	02 Dec 2022 11:33
URI:	https://orca.cardiff.ac.uk/id/eprint/8161

Citation Data

Cited 147 times in Scopus. View in Scopus. Powered By Scopus® Data

Actions (repository staff only)

Edit Item