齿轮稳态温度场及热变形研究

根据摩擦学、传热学以及齿轮啮合原理等知识,确定了轮齿各表面的对流换热系数的计算方法,及啮合面摩擦热流密度的计算方法.利用APDL语言建立了单齿热力耦合分析的有限元参数化模型.引进了混合介质特性参数的比例因子及修正系数,使得有限元模型更加接近实际工况.得到了齿轮单齿稳态温度场及热变形的有限元分析结果.并通过数据处理得到了啮合面热变形量沿啮合线法线方向的变形曲面.研究结果表明:齿轮的稳态温度场存在明显的温度梯度,啮合面温度最高,最高温度出现在啮出端双齿啮合区中部.齿轮的热变形存在明显的变形梯度,齿顶变形量最大,齿根最小.热变形沿啮合线法线方向的变形量,在齿顶中部最大,在齿宽方向成上凸分布,且在齿顶位置上凸最明显;在量级上与齿廓修形的修形量处于同一量级,因此将对齿廓修形的效果产生很大影响.本文的研究可为考虑热变形的齿廓修形设计等提供理论依据.

Study on Steady-state Temperature Field andThermal Deformation of Gear

The convective heat transfer coefficient of different tooth surfaces and the friction heat flux density were identified based on the theory of tribology,heat transfer and gear meshing theory.The parametric model of finite element thermal analysis of single tooth was established by using APDL.The ratio factor and correction factor of mixed medium characteristic parameters were proposed.The steady-state temperature field and the thermal deformation of the single tooth were obtained.Through the data processing,the deformation surface along the normal direction of the meshing line was obtained. Results showed that the steady-state temperature field obviously had the temperature gradient.The highest temperature surface was the meshing surface,and the highest temperature emerged in the middle part of the upper double teeth meshing area.Thermal deformation of gear obviously had deformation gradient,the addendum''s was the maximum,and the dedendum''s was the minimum.The deformation along the normal direction of the meshing line had a convex distribution in the direction of tooth width,and the maximum value emerged in the middle of the addendum.The thermal deformation and the amount of the tooth profile modification were almost in the same order of the magnitude,therefore,it will have a great influence on the tooth profile modification.The research can provide the theoretical basis for the design of tooth profile modification considering the thermal deformation of gear.