多隧洞输水工程进水口整流措施研究

多隧洞输水工程进水口控制段布置不合理往往会引起各隧洞分流不均,从而导致过流能力不足或空气进入有压隧洞的问题。以某水资源配置工程的倒虹吸为例,针对其进口控制段分流不均的现象,通过模型试验进行了分流墩、整流池以及底坎与整流池组合等整流措施的研究。试验成果表明:分流墩结构型式简单,利用其导向功能可较好地解决两洞分流不均问题;整流池通过改变水流的急缓流状态实现水流的横向均化,可达到多隧洞均匀分流的目的,但需要较长的池长,经济性略差;整流池与底坎组合措施横向均化水流的原理和效果与整流池相同,加设底坎可较大程度地缩短池长,其经济性较优。

Research on flow streamlining technology for water intake in multiple-tunnels water conveyance project

In water conveyance projects with multiple-tunnels, unreasonable control section layout at the water intakes may cause uneven discharge distribution of every tunnel, which will bring about the problems such as insufficient discharge capacity or air entering into the pressure tunnel. In this paper, for an inverted siphon of a water resources allocation project, due to the uneven discharge distribution at the control section of the intake, physical model experiment was carried out to research the flow streamlining measures such as diversion pier, flow streamlining pool and combination of bottom sill with streamlining flow pool etc. According to the research results, the diversion pier has simple structural type and its guiding function can solve uneven discharge distribution problem of the two tunnels efficiently. The streamlining-flow pool can regulate the flow distribution in transversal direction to meet the even discharge distribution requirement of multiple tunnels by regulating the tranquil flow and rapid flow, but it has poor economy due to the long pool length. Combination of bottom sill and flow streamlining pool has the same principle and effectiveness with the streamlining flow pool, and it has good economy as it could reduce the pool length efficiently by the sill layout.