基于水力控制的分段低压输水系统优化研究

Optimization on the Stepped Low-pressurized Water Diversion System Based on Hydraulic Control

分段低压输水系统是一种结构相对简单,采用分段降低水头的新型自流有压引水结构,而保水堰则是分段低压输水系统的关键建筑物。通过建立保水堰关闸检修的数值仿真模型,对保水堰的堰流、井流等复杂流态进行了模拟,仿真结果表明在检修闸门和下游管涵之间设置调压柜或明渠段等减振结构可以减小检修过程中的剧烈水位波动,并对调压柜和明渠段的减振效果作了比较。研究还发现若减振结构的面积设置不当,会引起下游输水单元的水力共振。在水力控制和分析的基础上,提出了保水堰及减振结构的整体优化设计原则,为工程设计提供了技术依据,有较大的推广应用价值。

The stepped low-pressurized water diversion system is a new type of gravity water supply system, which is simple in structure and water conservation weir is the pivotal structure. In this paper numerical models for unsteady flow result from inspection are established to simulate the overfall and well flow patterns respectively. The result of numerical simulation shows the surge-chamber or open-channel set between the bulkhead gate and downstream pipeline can alleviate hydraulic oscillation resulted from inspection. Then the alleviation effect is compared between the two alleviation sets. The research also find out that the improper area of alleviation set can enlarge hydraulic oscilla- tion of the water level of downstream conservation weir well. At last, based on hydraulic control and analysis, the principle of optimization to water conservation weir well and alleviation sets is proposed. All the researches above can offer technical grounds for the design, meanwhile the optimization principle has broad application value.