Study On Hydraulic Characteristics Of A Turning Drain Tank

The drain is widely used in various water conservancy projects because of its simple structure and good drainage effect.Most of the draining tanks are usually equipped with straight grooves,and outflow usually flows into the river by setting up retaining walls.When the upstream water level is relatively high,the discharge velocity is relatively large,so that the flow has greater energy,which will cause a hidden danger to the retaining wall and the downstream channel.Therefore,at higher water level discharge,it is necessary to focus on how to dissipate the discharge water and effectively guide the river to the downstream channel.In this paper,a new type of efficient energy dissipator is proposed by optimizing the energy dissipation facilities of the turn discharge trough,and its hydraulic characteristics are studied.Based on a practical water conservancy project,the hydraulic characteristics of different schemes of the turning drain are compared and analyzed.The physical model test was used to verify the discharge capacity of the discharge tank of the flood water level,and the hydraulic parameters,such as the water surface line,velocity and pressure in the discharge tank,were tested and analyzed.On the basis of guaranteeing the downstream safety,the energy dissipation effect of different schemes is compared and analyzed synthetically,and a new type of high efficiency energy dissipator suitable for the turning discharge tank is put forward.The reliability of the physical model test results is verified by FLUENT numerical simulation.The main research results are as follows:(1)summarize the domestic and foreign scholars' research status on discharge water discharge project,especially pay close attention to the research on energy dissipation and anti flushing at the end of the discharge tank and the optimization measures,compare the advantages and disadvantages of different energy dissipation methods of the discharge buildings,and study the new type of energy diversion and energy dissipation requirements.The effective energy dissipator can design the size of the energy dissipator reasonably.(2)physical model tests were carried out on the drainage scheme of the drain tank including the original design scheme and the optimization scheme in 17 schemes.In the original design,there is an angle between the outlet of the drain and the direction of the river,and the long-term erosion of the water will cause erosion risk to the retaining wall.In the optimization scheme,the outlet of the discharge tank is turned,and the steering diversion pier is added to the bucket to make the flow of water flow effectively,on the other hand,the additional energy dissipation effect is achieved.The study shows that after optimizing the flow pattern,the flow is smoothly connected,the downstream river bed scouring degree is weakened,and the energy dissipation effect is good.(3)FLUENT numerical simulation software is used to carry out numerical simulation of the drainage tank.The 3D model is drawn in the 3D CAD software,then the model is introduced into the ICEM-CFD to divide the grid and check the quality of the grid.The generated grid is introduced into the FLUENT,the boundary conditions are set up,the water discharge trough of the original design scheme model and the optimized scheme model is calculated,and the discharge,water surface line,flow velocity and pressure are given.Finally,the energy dissipation effect of the final optimization scheme is analyzed and demonstrated.Finally,the FLUENT simulation results are compared with the physical model test results,and the two conclusions are basically the same.The new energy dissipator of the diversion and energy dissipation of the water conservancy project has effectively solved the hidden danger of the discharge building,and has a reference value for the design and theoretical research of the energy dissipator of the water conservancy project.