核电循环泵行星齿轮热弹流润滑研究

核电齿轮箱的良好润滑性能是核电循环泵可靠运行的重要保障，充分考虑齿面形貌和齿廓修形等因素对内/外啮合齿轮副的影响是准确评估其润滑特性的前提。建立典型工况下核电循环泵行星传动系统斜齿轮热弹流润滑模型，首先将斜齿轮副的啮合状态几何等效为圆锥滚子的接触问题，然后考虑斜齿轮接触变形和齿廓偏差，计算得到内/外啮合齿轮副接触区域不同位置的油膜厚度、承载压力、摩擦应力和闪温等参数。考虑齿面磨合作用，采用移动平均滤波方法对未经磨合的初始形貌进行光滑处理，分析了齿面形貌对润滑行为的影响，最后采取齿廓修形改善润滑特性。结果表明：粗糙度和齿廓修形均会对润滑特性产生明显的影响，齿面粗糙形貌会造成油膜厚度减小，进而影响其润滑特性，弱化润滑油膜的承载能力；通过齿廓修形可以改善齿轮啮合边界处的几何过渡，降低该区域的应力集中和表面温度，从而明显改善啮合线终端的润滑状态。

Study on Thermal Elastohydrodynamic Lubrication of Planetary Gears in Circulating Water Pump of Nuclear Power Plant

The good lubrication performance of the nuclear power gearbox is an important guarantee for the reliable operation of the nuclear power circulating pump,and the fully considering the influence of tooth surface morphology and tooth profile modification on internal and external meshing gear pairs is a prerequisite for accurately evaluating lubrication characteristics.The thermal elastohydrodynamic lubrication model of the helical gears of the planetary transmission system in the nuclear power circulating pump was established under typical working conditions.The meshing state of the helical gear pair was geometrically equivalent to the contact problem of a conical roller,and by considering the contact deformation and tooth profile bias of the helical gears,the oil film thickness,lubrication pressure,friction stress,and flash temperature at different positions in the contact area of internal and external meshing gear pairs were calculated.Considering the tooth surface running-in effect,the moving average filtering method was used to smooth the initial morphology without running-in,and the influence of the tooth surface topography on the lubrication behavior was analyzed.The tooth profile was modified to improve the lubrication characteristics.The results show that surface roughness and tooth profile modification have significant influences on lubrication performance,and the rough morphology of the tooth surface can cause a decrease in oil film thickness,so as to affect the lubrication characteristics and reduce the load-bearing capacity of the oil film.By modifying the tooth profile,the geometric transition at the gear meshing boundary can be improved,the stress concentration and surface temperature in this area can be reduced,and the lubrication state at the end of the meshing line can be significantly improved.