大型复杂河网一维动态水流-水质数值模型

建立了非恒定河网一维水流-水质数值模型（THU-River1D）,水动力模块利用最近提出的汊点水位预测-校正（junction-point water stage prediction and correction,JPWSPC）法处理缓流河网汊点处的回流效应,采用Preissmann格式离散Saint-Venant方程组,并采用Newton-Raphson方法求解非线性离散方程;水质模块采用分步法,分别求解对流项、源（汇）项、以及纵向离散项,其中,对流项处理采用改进的四阶显式Holly-Preissmann格式。模型无需特殊的河道编码,既适用于树状又适用于环状河网,还适用于潮汐流动。

One-dimensional hydrodynamic-water quality model for large complex river networks

A one-dimensional hydrodynamic and water quality model for river networks is developed using a newly proposed method of junction-point water stage prediction and correction(JPWSPC) for calculation of backwater effects at junctions.In the hydrodynamic module,the Saint-Venant equations are discretized with Preissmann scheme and the nonlinear equation system is solved by Newton-Raphson method.In the water quality module,an operator-splitting method is adopted to calculate the advection,source(sink) and longitudinal dispersion terms of pollutant transport equation,and the advection term is discretized with an improved explicit Holly-Preissmann scheme of fourth order.The model is applicable to river flow and tidal flows in a dentritic or looped channel networks,with no need of specific node-numbering.