| China’s railways are increasingly developing in the direction of rapid passenger and heavy cargo.As an important means of transportation for railway transportation,locomotives play an important role in the rapid development of national economy and society.HX_D3D series locomotives serve on ballasted lines with harsh basic environment and complex lines.Various contact problems occur frequently,and the probability of repairing and changing wheels remains high.The classical contact mechanics theory can no longer be used to solve some specific problems arising from the wheel-rail contact process.Researchers have employed finite element software to demonstrate the various origins of rolling contact fatigue in various urban rail systems and transportation systems,due to the advancement of computer performance.systems.The finite element method is also one of the main ways to solve the problem of wheel-rail relationship.In this study,the static and transient analysis of wheel-rail contact was carried out by using the large finite element software ABAQUS in the parallel computing environment,and the fatigue life was predicted by using Fe-safe software.The specific research work is as follows:(1)Establishing a wheel-rail contact CAE model,based on the data and finite element software,was done using the wear-type wheel of the HX_D3D locomotive and the standard 60steel in China as the research object.Calculating the static strength of the wheel and axle in three working conditions of straight line,curve and turnout,the UIC510-5 is then employed to verify it.Results demonstrate that the wheel and axle’s maximum stress values,under the three working conditions,do not surpass the material’s yield strength,and their strength is in accordance with the requirements.(2)The aim is to construct a finite element representation of wheel-rail contact to explore the characteristics of its power.An exhaustive examination of the static contact between wheel and rail,in terms of lateral displacement of the wheelset,axial load,yaw angle,wheel-rail contact stress,transverse and longitudinal length and area shape of the contact spot,is conducted.Additionally,a comprehensive analysis of the variation law with various parameters is conducted.The research shows that when the lateral displacement changes,the lateral and longitudinal lengths of the contact spot will complement each other.When the axle load increases,the wheel-rail contact stress will also increase accordingly,with an increase of up to9%;when the transverse displacement remains unchanged and the yaw angle changes,the transverse and longitudinal lengths of the contact spot are almost stable.(3)The contact strength under dynamic load caused by wheel-rail contact failure is studied.A finite element model of wheel-rail rolling contact is constructed to evaluate the alteration of contact stress under varying axle load and friction coefficient.The simulation analysis and calculation of the load under the non-circular excitation of the wheel such as peeling and polygon are carried out.Using finite element software,the wheel’s fatigue strength is assessed and the rolling contact fatigue life of the wheel duo is evaluated.The results show that when the frequency is close to 1000Hz,the possibility of resonance is greater,and it is very likely to increase the stress level of the wheel and cause the wheel to be out of round in advance.The maximum strain position on the wheel surface will not change with the change of axle load.Due to the accumulation of plastic strain during wheel-rail rolling contact,these positions will be continuously affected by cyclic load,resulting in micro-cracks at the strain position,The performance and service life of wheel-rail should be taken into account when analyzing the fatigue life of its rolling contact,which will have an effect. |
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