管渠结合系统非恒定流数值模拟及理论分析

管渠结合系统非正常运行工况闸门突然关闭时,最大壅水高度的计算对渠堤及闸门的设计具有重要意义。上下游闸门同时关闭时,管渠结合系统最大壅水高度值存在直接水位波动和间接水位波动两种类型,并有其判别方法。有压管相对较长时,明渠和有压管段均可划分成微段联合计算,全面阐述了这种情况下用特征线法数值模拟时内边界条件的处理方法。经系列计算检验,说明该方法是合理、有效的。

Theoretical Analysis and Numerical Simulation for Unsteady Flow in Pipe-Canal Combined System

When the gate of the pipe-canal combined system is suddenly closed under non-normal operating conditions,calculation of the maximum backwater height has important significance on the canal bank and gate design.When upstream and downstream gates are simultaneously closed,the maximum backwater height of the pipe-canal combined system also has direct and indirect water level fluctuations,as well as their identification methods.When the pressure pipe is relatively long,the open canal and pressure pipe are divided into micro-segments and jointly calculated.Under the circumstances,the method of processing internal boundary conditions was comprehensively expounded based on numerical simulation using the characteristic line method.A series of calculations and tests show that the method is reasonable and effective.