混合润滑下螺旋锥齿轮抗胶合能力分析

针对螺旋锥齿轮重载下热胶合失效问题，对螺旋锥齿轮在混合润滑条件下的摩擦热行为进行分析. 通过混合弹流润滑数值计算方法和基于有限元的热分析方法，综合考虑螺旋锥齿轮的表面粗糙度、载荷分担、速度矢量和真实接触几何等因素建立点接触混合润滑分析模型，计算啮合轨迹上的连续摩擦系数变化和摩擦热流率，采用有限元分析软件进行齿面热载荷的加载，考虑轮齿导热和齿面与环境的热对流，分析轮齿本体温度场分布和啮合过程中闪温变化. 根据齿面最大接触温度与国际标准ISO 6336-20中齿轮抗胶合能力计算方法进行比较分析. 结果表明：有限元热分析得到的齿面温度与ISO所得变化规律十分接近，其最大温度低于ISO标准计算温度，使用ISO标准计算出螺旋锥齿轮抗胶合安全系数小于有限元法. 在混合润滑下求解的齿面热流率和温度变化，并且考虑了齿轮热传导和热对流影响，从理论上来说有限元法更加符合实际工作情况. ISO方法在处理上述问题以及计算本体温度上仍有不足，但其在齿轮抗胶合能力校核上具有广泛的适用性，可考虑结合有限元热分析法解决传热问题同时进行抗胶合能力综合评价.

Aiming at the thermal scuffing failure problem of spiral bevel gears under heavy loads, this study analyzes the frictional thermal behavior of spiral bevel gears under mixed lubrication conditions. By combining the numerical calculation method of mixed elastohydrodynamic lubrication and the finite element-based thermal analysis method, a point-contact mixed lubrication analysis model is established by comprehensively considering factors such as the surface roughness, load sharing, velocity vector, and real contact geometry of spiral bevel gears. The continuous variation of friction coefficient and frictional heat flux along the meshing trajectory are calculated. Finite element analysis (FEA) software is used to apply the thermal load on the tooth surface. Considering the heat conduction of the gear teeth and the thermal convection between the tooth surface and the environment, the temperature field distribution of the gear body and the flash temperature changes during the meshing process are analyzed. Comparative analysis is conducted based on the maximum contact temperature on the tooth surface and the gear scuffing load capacity calculation method specified in ISO 6336-20. The results show that the tooth surface temperature obtained by finite element thermal analysis has a variation trend very close to that obtained by the ISO method, and its maximum temperature is lower than the temperature calculated by the ISO standard. The scuffing safety factor of spiral bevel gears calculated using the ISO standard is smaller than that obtained by the finite element method. By solving the tooth surface heat flux and temperature changes under mixed lubrication, and considering the effects of gear heat conduction and thermal convection, the finite element method is theoretically more consistent with the actual working conditions. The ISO method still has shortcomings in dealing with the above problems and calculating the gear body temperature, but it has wide applicability in the checking of gear scuffing load capacity. It is recommended to combine the finite element thermal analysis method to solve the heat transfer problem and conduct a comprehensive evaluation of scuffing load capacity simultaneously.