洪泛区河网非恒定水沙数学模型的研究

鉴于江河流域中下游地区交错复杂的河网体系 ,本文建立了适应性强的复杂河网区非恒定水沙数学模型。模型中采用汊点分组方法求解水流方程组 ;选用了与实际情况较为吻合的汊点分沙求解方法 ,建立了分洪口门修正模式 ,采用适合于复杂流动状态下泥沙方程组的求解方法。同时为了提高模拟精度和扩展模拟功能 ,对河网中蓄水汊点和分蓄洪区的水流运动模拟等环节提出了合理可行的数值处理方法 ,并提出了河网水沙运动模拟中进一步需要研究的问题。最后把本文所建模型应用于汉江杜家台分蓄洪区的水沙运动模拟

Numerical simulation of sediment transport in unsteady flow of river networks in flood plains

Due to the complex flow condition of the networks in the middle and lower reach in most rivers,a numerical model of flow and sediment movement in river networks has been proposed. A junction group method,which is based on gradation method,is applied to solve the flow matrix equations. In this model,the solving method of sediment transport equations under complex flow conditions has been presented,including sediment distribution method at junction nodes,and modification model at flood diversion gate.Meanwhile,other techniques,such as how to handle junction nodes that can reserve water and sediment deposition have been used.Finally, data of Dujiatai in the HanJiang River has been adopted to verify the model,and further study need in the model has been presented.