2002 Volume 39 Issue 2 Pages 117-123
This paper presents details of a second order accurate Godunov-type numerical model of the two-dimensional shallow water equations and shows the application of the model to flow in a vertical sIot fishway. The model employs Roe's flux function for the convection tems and a non-linear slope limiter to prevent unwanted spurious oscillations. The model is also based on quadtree grids that adapt to inherent flow parameters, such as depth-averaged vorticity. Three test cases are demonstrated using a typical vertical slot fishway. The first test case uses relative coarse numerical grids and the second uses fine grids. The third one uses solutio-adaptive grids. Comparing the results between the first and second cases, it is shown that the results largely depends on the size of grids in interior flow region, even though the flow boundaries are fitted correctly by quadtree grids. Through the comparison between the results of second and third cases, the advantage of solutio-adaptive grids is demonstrated.
