Research on flow streamlining technology for water intake in multiple-tunnels water conveyance project
WANG Haibo;JIANG Zhibing;CHENG Zibing;Hubei Provincial Water Resources Hydropower Planning Survey and Design Institute;Department of Hydraulics,Changjiang River Scientific Research Institute;
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.