Study On The Hoisting Force And Stability Of The Plane Gate Located In The Middle Of Long Water Delivery Tunnel

The estimation of gate opening and closing force is important for the choice of gate hoist,which is the precondition of the gate normal operation.The stability of the gate in the closing and openning process of dynamic water is guarantee for the gateworking safty.The pressured plan gate is influnced by many factors in the process of closing and opening,which is the key and difficult points in the hydraulic gate design.Most predecessors have researched on the hoisting force of the common pressured plane gate,but plane gate in the middle of long pressure tunnel is less mentioned.It is difficult to study by numerical model for the complexity of the hydraulic conditions and uncertainty of hydraulic parameter.This article is based on two practical engineering,through the establishment of hydraulic model tests to study the characteristics of opening and closing force and the operation stability of the plane gate in the middle of long pressured tunnel.The main results are as follows:(1)Two 1:25 scale models were built following the gravity similarity criterion.The two types of long pressure tunnel gates closing and opening force in hydrodynamic conditions were studied.It showed that:thecapability of the hoist can meet the requirement for the Xianlin control plane gate;The hoisting force changes greatly within the scope of the small opening degree and the maximum hoisting force occurres near the relative opening degree of 0.05;The opening and closing force of Maerdang flood discharge emergency gate was closely related to the flow regime under the brake and we took messure of gaining additional weight for the gate can't close down safely in designed conditions.(2)Based on two actual engineering,the two hydraulic models of The thousand island lake long water conveyance tunnel Xianlin control brake and Maerdang flood discharge emergency plane gate were built.It's to study whether the bottom girders cutouts can reduce the dynamic water opening and closing force of the gate in the long pressure tunnel.The resuls showed that the bottom girders cutouts was not obvious for the gate located in the middle of long water delivery tunnel.(3)For the Xianlin control plane gate,which located in the long water tunnel,the plane gate's working stability is studied.Mainly through the following three aspects analyzed:Establish a three finite element numerical model of the plane gate for modal analysis;Study on the fluctuating pressure characteristic on the panel and bottom edge of the gate;Through the calculation of numerical model combined with physical model test,this artical have studyed the flow-induced vibration response of the plane gate in dynamic water.