Study On Hydrauliic Characteristics And Shape Optimization Of Diversion Tunnel In Ertanggou Reservoir

Diversion spillway is a commonly used water discharge structure in hydraulic structure.In the actual project,the diversion tunnel is often limited by the conditions of geology,topography,engineering structure and the overall layout of the project hub,and its body design form also changes.The design of the diversion tunnel has a great influence on the flow and hydraulic characteristics of the discharge.Therefore,in order to obtain more reasonable design results,through the physical model test and numerical simulation,the diversion tunnel is reasonable,and the reasonable design scheme of diversion tunnel is obtained.In this paper,a large number of literatures,theoretical analysis,physical model tests,numerical simulations,and the main points of the hydraulic characteristics of diversion spillway are studied.Based on the actual diversion tunnel of Ertanggou reservoir,The flow pattern,the water line,the pressure and the flow rate during the flood season and the water storage period are reasonable after two body sizes.The research results and conclusions of this paper are mainly reflected in the following aspects:(1)Comprehensively expounded the theoretical basis of the research on the diversion tunnel of the hydraulic structure,the research status of the related fields are expounded at home and abroad,including the current research methods of the hydraulic characteristics of the diversion tunnel,the latest research progress of eliminating the cavitation erosion of the discharge structure,research on relevant fields at home and abroad can learn from experience.(2)Based on the analysis of the layout,the geological and terrain conditions of the Ertanggou reservoir project.The hydraulic model is constructed based on the preliminary design scheme,the purpose is to judge whether the original design scheme can meet the hydraulic characteristics.The results show that the original design scheme is poor in flow pattern,and the far-reaching water jumps are generated.(3)From the original model test conclusions and suggestions,optimization of diversion tunnel design,reduce the parabolic section of curvature,reduce the power pool floor elevation,the purpose is to optimize the discharge flow,to prevent cavitation flow The results show that the flow regime is obviously improved,the pressure value of the bottom plate and the wall is larger,and the probability of cavitation damage is reduced after two optimization.(4)According to the reasonable scheme of diversion tunnel from the model test,Based on the numerical simulation software,the RNG model and VOF of free surface tracking method was used for two-dimensional numerical simulation of the parabolic segment,defogging pool segment,The results show that the model test and numerical simulation are in good agreement.The research topic provides the theoretical basis for the diversion tunnel design of Ertanggou reservoir,which effectively protects the normal construction of the water conservancy project and promotes the normal operation of the later reservoir.At the same time,the topic for optimization design of the same water conservancy project can provide a more reliable experience support.