Prediction And Dynamic Analysis Of Wheel And Rail Wear Based On Multivariate Calculation

In recent years,with the rapid development of China's railway industry,the safety and economic problems in the process of railway operation become increasingly prominent.In particular,the problem of wheel-rail abrasion has been widely studied.As a common problem in wheel-rail relationship,this problem not only affects the reliability and stability of wheel-rail relationship,but also has a great impact on the safety and operation cost of railway transportation.It is of great theoretical and practical significance to study and master the characteristic law of wheel-rail abrasion for the development and operation of China's railway industry.In this paper,the development and current status of wheel wear research at home and abroad are discussed,and the purpose and significance of wheel wear prediction research are clarified.Based on the theory of vehicle system dynamics,three-dimensional wheel and rail contact theory and the theory of material wear strength,a prediction model of wheel and rail wear of railway vehicles was established in UM multi-body dynamics software.The model includes a truck and vehicle model with K6 bogie and C64 multi-rigid-body system with 66 degrees of freedom.This paper firstly discusses the development process and current situation of wheel wear research at home and abroad,and clarifies the purpose and significance of wheel wear predicttion research.Based on the theory of vehicle system dynamics,three-dimensional wheel and rail contact theory and the theory of material wear strength,a prediction model of wheel and rail wear of railway vehicles was established in UM multi-body dynamics software.The model includes a truck and vehicle model with K6 bogie and C64 multi-rigid-body system with 66 degrees of freedom.Simulation of the distribution of curvature radius in the actual line line model and the track irregularity excitation;Based on the material loss theory proposed by J.F.Archard and the contact force model proposed by w.Kik and j.Piotrowski,a multi-variable calculation(MVC)model with the same iterative structure and different external configuration conditions was established to predict wheel and rail wear.The wheel-rail abrasion simulation model is simulated in the range of 100,000km.The multi-variable combination of different speed grades and different curvature radii is included to obtain the wheel-rail abrasion profile under different operating mileage.Wheel profile abrasion:the abrasion range is mainly distributed in the area of the flange curve and the circumference of the tread.The variation of the abrasion range is not obvious with the increase of the mileage,and the tread abrasion shape has a similar rule.Rail abrasion:the left rail abrasion mainly occurs on the rail surface and side transition surface,and the abrasion range is between-15mm and 35mm.The wear depth ranges from 0 to 1.45mm.The right rail wear mainly occurs on the rail surface,and the wear range is-35mm-35mm.The wear depth ranges from 0 to 0.75mm.The change of the contact parameters of the wheel and rail:the contact Angle decreases with the wear intensity of the wheel and rail;With the increase of operating mileage,the equivalent taper tends to increase and fluctuates.The dynamic indexes of different speeds before and after wheel and rail abrasion were calculated and analyzed.The results show that the critical speed of the vehicle decreases with the increase of the wear rate,and the lateral vibration characteristic of the wheelset snakes in the limit cycle under the condition of running higher than the critical speed;The dynamic performance indexes of vehicles on straight line,R600m and R10OOm curve lines are affected by wheel-rail abrasion.