Study On Aerodynamic Load And Stress Response Of 400 Km/h High Speed Train Equipment Cabin

With the increase of train speed,the aerodynamic load has more and more significant impact on the car body and the equipment cabin under the car.Fatigue cracks begin to appear on the apron board,bottom plate and bracket of the equipment cabin,which seriously affects the safety of high-speed train.Therefore,the research on aerodynamic load of the equipment cabin should not be neglected.In this paper,the research object is the aerodynamic load of 400 km/h high-speed train equipment cabin.Using both measured and simulated methods,the aerodynamic load and stress response of equipment cabin of 400 km/h high-speed train under different working conditions are obtained through tracking test and processing of measured stress data,CFD numerical simulation and finite element analysis.The following conclusions are obtained through the study:(1)Based on the track test data of China Standard EMU,the stress-time history of each measuring point is obtained by processing the measured data of the concerned position.Combining the velocity signals,the stress amplitude and stress spectrum of each module of equipment cabin under different speed levels are obtained.(2)Based on CFD fluid dynamics numerical simulation analysis theory,the aerodynamic model of high-speed train under open air condition and train meet conditions is established,and the aerodynamic loads of high-speed train under different conditions are simulated.The pressure distribution of the car body and equipment cabin at different speed levels is obtained under the open air conditions,and the pressure curves of apron board and bottom plate of equipment cabin from head to tail under the 400 km/h open air condition are further analyzed.Under the condition of constant speed meeting,the pressure distribution on the surface of car body and equipment cabin at different times of meeting is obtained.And setting up monitoring points for equipment cabin.Different positions’ pressure curve,and peak,trough and amplitude of pressure wave during tarin meeting under 400 km/h are obtained.It can be seen that the pressure in most positions of equipment cabin are negative pressure,and the amplitude of pressure fluctuation increases with the increase of the speed of the meeting.During the same speed train meeting,the amplitude of pressure wave on the head car of equipment carbin is larger than that of the tail car.(3)Establish finite element model of equipment cabin,the stress response of its aerodynamic load is studied.The finite element model is established by modules.T aerodynamic loads at different positions of each module under different speed levels s extracted from CFD numerical simulation analysis and load the modal The stre nephogram of each module of equipment cabin is obtained.And the measured stre amplitude is compared with the simulation results.The relative error is within t allowable range of 10%and it verify the validity of the simulation calculationThe above research provides a method for design and test evaluation of equipme cabin of 400 km/h high-speed train.And it lays the foundation for the establishment the load spectrum.