频繁启停工况下轮轨滚动接触磨损行为与磨屑颗粒排放特性研究

Study on Wear Behavior and Debris Particles Emission Characteristics Induced by Wheel-rail Rolling Contact under Frequent Start-stop Conditions

轨道交通车辆在近站点附近须频繁启停,在加减速过程中轮轨界面接触应力分布变得更为复杂,从而引起轮轨磨耗和磨屑行为的改变。为深入了解近站点附近频繁启停工况下轮轨滚动接触界面的磨损特性与颗粒物排放行为,利用自行研制的JD-DRCF/M型轮轨滚动接触疲劳/磨损试验台开展了频繁启停工况下轮轨循环加减速磨损试验与颗粒物排放实时监测。结果表明,轮轨间黏着系数受加速度α_(r)的影响显著;随着加速度α_(r)的提高,加速阶段完成后的黏着系数依次呈现先下降后上升的趋势;适中的加速度(如α_(r)=800 r·min^(−2))降低了轮轨间黏着,同时有效减缓了轮轨磨耗;启停工况(即有加速度时)大大提高了可吸入颗粒物(如3.0≤d≤10.0μm)的排放浓度,尤其在较低的加速度(如400 r·min^(−2))工况下这种现象更为严重。

Rail transit vehicles are subject to frequent stops and starts near stations,the contact stress distribution between the wheel-rail interfaces become more complex during the process of acceleration and deceleration,which leads to unusual wheel-rail wear and debris behavior.An innovative wheel-rail rolling contact fatigue and wear test rig JD-DRCF/M is developed to carry out the cyclic acceleration and deceleration wear test for the wheel-rail rolling contact tribo-pairs and real-time monitoring of particle emission under frequent start-stop conditions,to understand the wear behavior and particle emission characteristics of the wheel-rail rolling contact interface near the station.The results showed that,the adhesion coefficient between wheel and rail is significantly affected by the acceleration α_(r).With the increase of the acceleration α_(r),the adhesion coefficient after the completion of the acceleration stage showed a trend of gradually decreased and then gradually rose.Moderate acceleration(e.g.,α_(r)=800 r·min^(−2))reduces the adhesion between wheel and rail interface,and mitigates the wear loss of wheel and rail effectively.The emission of inhalable particles(e.g.,3.0μm≤d≤10.0μm)is significantly increased under the start-stop condition(i.e.,the condition of acceleration).In especial,this phenomenon was more serious under the low acceleration condition(e.g.,α_(r)=400 r·min^(−2)).