Study On Influence Of Channel Ice In Winter Operation On Water Diversion Channel

According to the needs of economic development,trans-basin water transfer project has become an important means to solve the disparity between the rich and the poor in the region and improve the ecological environment.In the western part of our country,because of the colder winter,the water flow in the water conveyance buildings will freeze.After the temperature drops below 0 degrees,the water will first appear in the water ice,ice water after the development of the formation of ice gradually formed,and then the accumulation of ice sheet formation.By the second year the temperature gradually increased and the ice caps began to melt,forming many different sizes of ice.These ice cubes collide with the side walls of open ditches as they flow along the water stream,resulting in the destruction of the side walls of the open channel.In a more serious situation,ice blocks will be formed,causing the destruction of water conveyance structures,threatening the lives and property of local people and the safe operation of water conservancy projects.In this paper,the influence of canal dredging on the open channel during winter operation is taken as the research object.Based on the existing researches both at home and abroad,the paper makes a comprehensive study through theoretical analysis,numerical calculation and indoor ice mechanics test.The impact of ice impact force on the open channel is studied,and the impact of ice impact force on the sidewall of the water channel is analyzed theoretically by using the symmetric penalty function in the contact-collision algorithm.Taking a section of rectangular open channel leading to the East Second Main Canal of Qin Project as an example,the failure mechanism of the open channel in water conveyance is analyzed.ANSYS software was used to establish the open channel model and the ice cube model.The unit was 3D solid 164 eight-node solid element,the material was defined as linear elastic material,the dividing channel of the open channel model was swept by grid,and the dividing ice model was mapped by grid.Contact type uses single-sided automatic contact.Set the boundary conditions and load.Solving using ANSYS own LS-DYNA SOLVER to solve.Post-processing using LS-PREPOST software to display the data and generate a variety of charts to analyze the different water flow velocity,different ice plane size,different ice thickness,ice collision angle under different conditions such as ice on the water channel Impact of impact.Subsequent indoor test,the use of ice hit the waterway open channel test multi-channel open channel slope diversion test device for experimental study.Simulate the whole process of the impact of ice in the open channel on the edge of water conveyance channel under the conditions of different flow velocity of ice,ice plane size,ice thickness and so on,collect the impact force data,deal with the data and numerical results.It is verified that the indoor test results are in good agreement with the numerical results.This shows that the numerical calculation is correct.The research in this paper provides theoretical basis and technical support for the design of the open channel for water conveyance in the cold arid regions of western China and the operation and management after its completion,which enriches the connotation of the ice mechanics experiment.