Thermal-Mechanical Coupling Analysis And Structure Optimization Design Of High-speed EMUB Rake Disks

Braking system is an important component of train and the brake disk is kernel module of foundation brake rigging.The brake disks that can convert kinetic energy of train to thermal energy which will dissipate to nature is carrying and transferred device of thermal cycle load,so the brake disks are subjected to vibrational fatigue failure on account of heat accumulation.Whether the brake disk is safety and stability or not directly affects the train safety.With the increase of the EMU speed,the fatigue damage of the brake disk increases significantly,causing serious economic losses and threatening the safe operation.For this purpose,taking the CRH380 BL brake disk as the research object,on the basis of referencing the domestic and foreign scholars' research,the paper carrys out thermal-mechanical coupling analysis and structure optimization design.According to accurate measurement of brake disk,using Solidworks 3D modeling software to solid modeling,and simplifying the model.The finite element model of brake disk is established by Hypermesh mesh generate software and Abaqus finite element analysis software.The results of thermal-mechanical coupling analysis show that,the material of brake disk meets the thermal and stress requirement under the condition of urgent braking which initial speed of braking lower than 300 kilometers per hour.Otherwise the paper contrasts the affection of temperature field and stress field between energy conversion method and friction power method.Using the revised Goodman-Smith fatigue limit diagram to evaluate the fatigue strength of brake disk,the selected points are all in the circle of envelope line,it shows that the fatigue strength of brake disk meets requirements.Using the four-point correlation method to estimate the thermal fatigue parameter of the brake disks' material.According to previous thermal-stress load spectrum,using Brown-Miller model modified by Morrow formula and Fe-Safe software estimates fatigue life of brake disk.When the initial speed of braking is 300 kilometers per hour,the minimum life of brake disk is estimated under friction power method and energy conversion method.After comprehensive analysis,friction power method should be widely used.Three briefly kinds of bionic heat radiation models are developed according to the structure of efficient material interchange of three kinds of species(e.g.banian,etc.),which can improve the heat dissipation of brake disk so as to prevent the wear and fatigue.The temperature field under the urgent braking condition which initial speed of braking is 300 kilometers per hour are researched and compared between the bionic and the cylindrical heat radiation brakes disks.Then using computational fluid dynamics software Fluent to calculate the distribution of heat radiation temperature in similar flow field condition.After comprehensive assessment,the platelike heat radiation is optimal choice of four heat radiations.