Author(s): Pin-Chun Huang; Kwan Tun Lee
Linked Author(s):
Keywords: Digital elevation model; Courant–Friedrich–Lewy stability condition; Computing efficiency; Diffusion-wave model; Kinematic-wave model
Abstract: Digital elevation model (DEM) is used to represent watershed topographic features in a raster or a vector data format, which has widely been linked with flow routing equations for watershed runoff modeling. In this study, a recursive formulation was encoded into each computational time step to permit a larger time increment in performing the kinematic-wave and diffusion-wave routing algorithms. To suit for the requirement of performing the recursive formulation, a novel routing sequence was developed to determine the cell-to-cell computational procedure in connection with the DEM database, in which the routing sequence can be set to follow either the grid elevation in a descendant order for the kinematic-wave routing or the water stage in a descendant order for the diffusion-wave routing. The proposed novel routing sequence was applied to a mountain watershed to show the computational efficiency. The result shows that the efficiency of the proposed algorithm was significant suppress than that of the conventional numerical algorithm especially for steep watersheds, in which the computing time was only one fifteenth in comparison with the conventional numerical method.
Year: 2013