基于温度场的磨齿热特性研究

根据七轴五联动螺旋锥齿轮磨齿机的结构模型和数控磨削原理,采用热传导和矩形移动热源理论及有限元分析方法,建立了磨齿温度场有限元分析3D模型和磨齿瞬态温度场。由此,对热和结构两个物理场进行耦合,仿真分析了磨齿瞬态热特性。实例分析表明,磨齿瞬态最高温度远高于磨齿稳态温度,且位于磨削弧中心;其它各点的瞬态温度,随位置、时间以及其它影响因素的不同,呈现不同的变化规律。磨齿瞬态热应力、热变形与磨齿瞬态温度密切相关,同时还受结构、材料特性和磨削条件等因素影响,磨齿瞬态最大热应力与热变形位于磨齿瞬态最高温度附近。在其它条件相同时,采用油基磨削液的瞬态最高温度、热应力与热变形均比采用水基磨削液时要大。这些研究为控制螺旋锥齿轮磨削质量以及磨齿热变形的修形提供了依据。

Research on Thermal Aspects of Grinding Tooth Based on Temperature Field

Based on the structure model and NC grinding principle of seven-axes and five-axes coordinate NC grinding tooth machine of bevel gear,this paper uses theories of heat conduction and moving rectangle heat source and the finite element method,and builds the finite element 3D model and transient temperature field of grinding tooth of bevel gear. Then by coupling of two physical field of thermal and structure,its transient thermal aspects are simulated and analyzed .The example analysis shows many conclusions of grinding tooth of bevel gear. Firstly,the highest transient temperature of grinding tooth is much greater than its static temperature,and its place of highest transient temperature is located at the center of grinding arc .As changing of the position, time and other factors,the transient temperature of other points has its different changing rule.Secondly,the transient thermal stress and deformation of grinding tooth are closely related to its transient temperature,and are still influenced by many other factors,such as the structure, material property and grinding condition of bevel gears .The greatest transient thermal stress and deformation locate at the area near the highest transient temperature .Finally, on the same of other conditions,the transient temperature, transient thermal stress and deformation of grinding tooth using oil-based coolant are all greater than that using water-based coolant .The research provides a foundation for the close control of precision grinding quality and the repairing of thermal deformation of bevel gear.