Experimental Study On Flow-induced Vibration Of Plane Straight-up Gate

Plane gate is one of the most common types of gates used in hydraulic engineering.It is a discharge structure and a water-retaining structure that can be used to control discharge flow in moving water or static water.It plays an important role in hydraulic engineering.Due to its own structural problems under the complicated hydraulic conditions,plane gates have many safety and stability problems in engineering applications.When the gate is opened,the gate structure is in direct contact with the water flow,and the flow of water has a surface force on the gate,causing vibration of the gate.Due to the interaction between the gate and the water flow,the gate may experience more intense vibration.When the primary frequency of the pulsation flow of the sluice gate is similar to or equal to the natural frequency of the gate,the gate will exhibit resonance instability.In severe cases,it may cause damage to the vibration of the gate.Therefore,starting from the fluid-structure interaction theory,using the fluid-solid coupling synchronization test method,it is of great significance to study the flow and the unsteady flow field of the complex flow field on the structure excitation problem.This paper researches and analyzes the flow-induced vibration of the gate through test methods.The main contents are as follows:(1)Establish a hydraulic model system,determine the test plan,check and debug the pulsating pressure sensor system,the triaxial acceleration sensor system,and the particle velocimeter system,specify the test conditions and test procedures,and conduct the test.(2)The post-gate velocity field is experimentally analyzed by means of a full three-dimensional particle velocity instrument PIV flow field test system.From the analysis of the experimental results,the evolution process of the vortex structure in the near-wall area of the gate plate and the vorticity field of the velocity field around the sluice gate can be obtained.Dynamic distribution characteristics provide a hydraulic basis for studying the causes of plane gate vibration(3)A test was conducted in a model tank and a fluctuating pressure sensor was used to study the fluctuating pressure characteristics of the flow under the conditions that middle section sink bottom sink point and side section under sink bottom measuring point of thebottom section of the sluice at the bottom of the sluice gate have plot and no plot under the different conditions.(4)Two acceleration sensors are arranged at the bottom of the middle section in the gate and at the bottom of the side section.By changing the opening degree of the gate and the flow rate at the gate,the accelerometer is used to measure the acceleration,velocity and displacement of the gate vibration.Through the vibration test and analysis system,the vibration characteristics of the gate in different operating conditions during the opening process are understood.