Simulation Study On Aerodynamic Characteristics Of High Speed Pantograph

With the running speed of train raised,the good contact between catenary and pantograph is the base to meet the quality requirment of current collection of high speed railway train except standard railway line and high-performing EMU vehicles.The dynamic performance between catenary and pantograph would reduce with the running speeding increasing,and the dynamic contact force cannot stay in the proper range.If the dynamic contact force between catenary and pantograph is too strong or too weak,it will influence the current collection quality,and even causes bad consequences.The high speed pantograph three-dimensional model was built by Catia in this thesis.Then ICEM is used to generate mesh of the simplified model and FLUENT is used for simulation of different working conditions.And the simulation data needs to be analyzed and post-processed.After making analysis of motion and dynamic of high speed pantograph frames and building the lift calculation model with equivalent two-dimensional frame of pantograph,the influence coefficient can be calculated.The influence coefficient shows the efficiency of the areodynamic drag and lift on collector head,upper arm,lower arm and lower pull rod transforming to the areodynamic lift of pantograph.Combining the simulation data with the influence coefficient,the areodynamic lift of pantograph and contact force between catenary and pantograph can be calculated.By means of LabVIEW,the post-processing mentioned above is carried out as a program.The calculation results are compared to relevant wind tunnel test data to prove the method in this thesis is correct.Different working conditions are studied including straight line without crosswind,passing through the tunnel and straight line with 10m/s crosswind.The simulation of every working condition is calculated at six speed levels as 160 km/h,180 km/h,200 km/h,220 km/h,250 km/h and 300 km/h.The raising height of pantograph is 1600 mm while calculating the working conditions of passing through the tunnel and straight line with crosswind.Besides,the main study objects of straight line without crosswind working condition are prototype pantograph and the pantograph after adjusting four-bar linkage,and two kinds of pantograph are simulated at five raising height which are 1200 mm,1600mm,2000 mm,2400mm and 2800 mm.Based on the simulation and calculation results,the areodynamic characteristics of pantograph can be studied.In addition,the different external factors and internal factors including different parts,different raising height and four-bar linkage adjustment how affect the areodynamic lift are analyzed.Furthermore,how the airfoil regulates the areodynamic lift is also studied,the simulation results showed airfoils with different shapes and different installation angle come into different regulating effects.