基于Preissmann全隐式河道演算的CASC2D模型研究

In order to reduce the computing time of CASC2D model which is a physically –based distributed hydrologic model, using Preissmann implicit scheme in dispersion the De Saint-venant equations is for channel flood routing, and compare with the original model based on explicit 1-dimensional finite difference diffusive-wave method. The flood simulation results in the Goodwin Creek watershed by implicit scheme and finite method are similar ,but implicit scheme is five times faster than finite method, so it has greatly reduced the running time of the model ,this is of great significance in real-time forecasting and the application by model on bigger basin.