Numerical Simulation Characteristics Of Snowpack On Standard EMU Bogies And Improved Design

When the EMU train is running at high speed in snowing frigid condition.The snow will accumulate on the bogie,which is under the body of the train.The disturbance of snowflake particles would adhere to equipments,surface,melt then freeze.Causing damage to the parts,make it difficult to maintain,and affecting the safety of train operation.Standard EMU is a new generation of high-speed train platform.All the researches and developments we did by ourselves,and fully up to the national standard for high-speed train manufacturing and design.Therefore,it's necessary and quite important to study at standard EMU bogie's adaptability,when it's working in the alpine region.This paper is based on the numerical simulation of standard EMU running at high speed on the snow covered rails using discrete phase model.Analyzed the flow field around the bogie and the adhesion characteristics of snow particles on each bogie components.Provided references for the further standard EMU bogie design and the solutions to snowpack reduction.The main research contents are as follows:(1)created a standard EMU computational model of three-train?the fine structure of the bogie and numerical calculation region,and bogie reserved the main components;(2)defined the physical parameters of snowflake particle?the discrete phase model and boundary conditions;(3)calculated and analyzed the flow field distribution around the standard EMU bogie,counted the snowflake particles adhesion on the surface of each bogie part;(4)improved the structure of baffles which are close to the bogie on standard EMU equipment cabin,compared and analyzed the flow field distribution around the bogie and the surface adhesion of snow particles before and after the baffle structure been optimized;(5)improved the structure of apron board of standard EMU,analyzed the influence of flow field and snow particle surface adhesion.The results showed:(1)the number of snowflake particles adhesion on the bogie parts were closely related to its surrounding flow field and air pressure difference.When standard EMU running at high speed in the windy and snowing condition,the trend of vertical pressure value on each bogie cross-section increased from bottom to top gradually;(2)the bogie structure of standard EMU is complex,its back baffle and the middle of the frame are easy to form vortex,snowflake particles always accumulated around here,(3)after the left and right sides of bogie apron board structure improved,the effect of snowpack reduction is efficacious.The snowflake particles adhesion on the 1?6 bogies and baffles all reduced,the decline range is 8.61%?94.12%.