Author(s): Junli Bai; Junhua She; Pengzhi Lin
Linked Author(s): Pengzhi Lin
Keywords: Shallow water equations; Curved river; Curved channel; One-dimensional array of data storage; Cartesian grid
Abstract: A numerical model is developed to simulate large-scale flow motion in curved channels and rivers. The model is based on the two-dimensional shallow-water equations. The model is solved numerically by using finite difference method constructed in Cartesian grid system that is easy to generate (compared to the unstructured grid system that may require complicated remeshing for solving inundation process problems), regardless of the complex natural river geometry. In the large-scale modelling of flows in a curved channel or river, the majority of Cartesian grids will be located on dry land that actually does not require computation, if the conventional two-dimensional array of data storage is used in the coding. In order to make the computation more efficient, a one-dimensional array of grid system is introduced that covers only the domain of interest. By doing so, computational resources (e.g., memory) could be saved in many realistic river modelling. The model will be first validated against laboratory data for turbulent flow in a curved channel. Finally, a case study of large-scale flow motion in a reach of Yangtze River will be simulated by using the proposed model.