Optimization Of Bogie Frame Structure For Hybrid Rail Vehicle

With the rapid development of China’s railway speed and high-speed railway,the demand for engineering rail vehicles is increasing day by day,and the requirements for the performance of rail vehicles such as running speed and construction capacity are also increasing.On the premise of increasing the speed of rail vehicles,the frame,as an important part of the bogie,its static strength and fatigue strength meet the specification requirements,which is very important for the operation safety of rail vehicles.On the basis of ensuring operation safety,optimizing the design of the frame and finally realizing lightweight is also an important research direction.Firstly,this paper summarizes the development status of rail vehicles at home and abroad and the application of structural optimization in the frame,and briefly introduces the finite element method and the related theory of structural optimization design.Taking the bogie frame of hybrid rail vehicle as the research object,on the basis of fully understanding the structural characteristics of the frame,the finite element model of the frame is established by using the finite element simulation software Hyper Mesh.The static strength under extraordinary load and simulated operating load is calculated according to the relevant specifications,and the fatigue strength of the frame is checked,which meets the requirements of the specifications.Then,on the premise of fully mastering the methods of topology optimization and size optimization,the structure of the frame is optimized by using Optistruct solver.The side beam and end beam of the frame are filled with 3D solid grid,and the three-dimensional models of the side beam and end beam are preliminary optimized based on topology optimization to remove redundant materials,so as to obtain the preliminary design scheme;According to the factors of actual processing and welding,two kinds of rib plate layout schemes are finally determined,and the size of the frame is optimized according to the two layout schemes,so that the weight of the optimized frame can be reduced again.Finally,the static strength and fatigue strength of the optimized frame are checked.The calculation results show that the static strength and fatigue strength of the optimized frame under various load cases meet the specification requirements.The maximum stress under extraordinary load case is basically the same.The difference between scheme 2 and the original frame under simulated operating load case 5 is less than 10 MPa.Compared with the original framework,the weight of scheme 1 is reduced by 154 kg,6.82%;Compared with the original framework,the weight of scheme 2 is reduced by 125 kg,5.54%.The frame weight difference between the two schemes is 29 kg.Compared with the rib plate layout of scheme 1,the rib plate layout of scheme 2 is more reasonable in the actual welding process.The above research provides some ideas for the lightweight of Railway Engineering Rail vehicle bogie frame in China.