Author(s): D. J. Zhu; Y. C. Chen; Z. Y. Wang
Linked Author(s):
Keywords: Subcritical flow; Channel network; Simulation; Implicit finite-difference; Junction-point water stage prediction and correction (JPWSPC) method
Abstract: A novel method is proposed for subcritical flow modeling in channel networks using the implicit finite-difference method which prevails in simulating gradually varied flows. The method is proposed to take account of the backwater effects at the junction points based on junction-point water stage prediction and correction (JPWSPC) and is applicable to flows in both looped and non-looped channel networks, even if the flows are tidal. The method is implemented in a numerical model, in which the Saint-Venant equations are discretized using the four-point implicit Preissmann scheme and the resulting nonlinear system of equations is solved using the Newton-Raphson method. The solving procedure has no difference from modeling single branches one by one except for simple junction-point water stage prediction and correction, which guarantees the simplicity, efficiency and robustness of the JPWSPC method. The model is applied to two hypothetic channel networks and a real river network in the south of China. All the networks are branched and also looped. Great agreement between the results and those from literature or observed data reveals the accuracy.
Year: 2009