采煤机摇臂齿轮固热耦合分析与齿廓修形

摘要

基于赫兹接触理论建立齿轮啮合力学模型,依据渐开线形成原理推导出滚动距离和滚动角变化规律,以牛顿冷却定律和傅里叶定律为理论基础,结合采煤机摇臂工作特性,对齿轮系统对流换热和摩擦热流量进行计算,在对流换热系数确定中综合考虑齿轮与润滑油,润滑油与箱体内壁,箱体外壁与外界空气的热传递特性,以Blok理论为基础,本体温度为初始温度,分析了齿轮表面闪温和接触温度随滚动距离及滚动角变化规律.采用Romax Design建立了采煤机摇臂齿轮传动系统模型,对惰轮轴齿轮副进行固热耦合分析,基于Romax微观几何修形理论对渐开线齿廓进行修形,分析了齿廓修形对温度场影响.结果表明:齿廓修形消除了赫兹接触应力瞬增现象,最大接触应力减少72 MPa,修形后高温区由齿顶和齿根向齿廓中部移动,改善了轮齿温度分布,最高温度降低31.4℃.为研究采煤机摇臂齿轮传动系统修形及优化提供了理论基础.%A gear meshing mechanical model was established on the basis of Hertz contact theory.The change law of roll distance and angle was derived according to the involute forming principle.Making Newton cooling theory and Fourier law as its theoretical foundation,the convective heat transfer and friction heat flow of gear system were calculated combined with the shearer ranging arm working characteristics.It is the first time that the convective heat transfer coefficient was confirmed by comprehensively considering the heat transfer characteristics of gear and lubricating oil,lubricating oil and box inner wall,box external wall and external air.Making Blok theory as a foundation,the bulk temperature was chosen as an initial temperature.The change law of gear surface flash temperature and contact temperature with the roll distance or angle was analyzed.The shearer ranging arm gear transmission system model was established by using Romax Design.Idle shaft gear pair solid-heat coupled characteristics was analyzed.Involute tooth profile modification and its influence on temperature field was analyzed on the basis of Romax micro-geometric modification theory.The results show that the Hertz contact stress transient increased phenomenon is eliminated and the maximum contact stress reduces 72 MPa by the tooth profile modification.The tooth temperature distribution is improved by the high temperature zone moving from tooth root and addendum to tooth profile central after the modification and the maximum temperature decreases 31.4 ℃.The results provide a theoretical foundation for analyzing the shearer ranging arm gear transmission system tooth profile modification and optimization.