Page 137 - 摩擦学学报2025年第9期
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第 9 期                      张玉言, 等: 环下润滑高速球轴承流固耦合传热特性研究                                      1391

                 that at lower bearing speeds, the self-rotation of rolling elements reduced the oil phase volume within the bearing cavity,
                 whereas at higher speeds, the opposite effect was observed. Additionally, the self-rotation of rolling elements decreased
                 their own temperature significantly. As the bearing speed increasing, the average oil phase area ratios in the raceway
                 wall surfaces decreased, while the average temperatures of both the inner and outer rings increased obviously and the
                 magnitude  of  temperature  rise  was  larger  for  the  inner  ring.  The  temperatures  of  the  inner  and  outer  rings  reached
                 minimum in the circumferential azimuth angle in front of the oil supply hole, gradually increased along the direction of
                 bearing  rotation,  and  reached  the  highest  in  the  circumferential  azimuth  angle  behind  the  oil  supply  hole.  With  an
                 increase in oil supply velocity, the average oil phase area ratios in the raceway wall surfaces increased, while the average
                 temperatures of the inner and outer rings first decreased and then increased. Furthermore, as the width of the bearing
                 cage increased, the oil phase in the inner ring decreased, while that in the outer ring increased. As a result, the average
                 temperature of the inner ring rised, while that of the outer ring decreased slightly. An increase in the pocket diameter of
                 the cage resulted in a slight rise in the average temperatures of both the inner and outer rings, because the average oil
                 phase area ratios in the raceway wall surfaces of both the inner and outer rings decreased. Lastly, with an increase in
                 cage thickness, the oil phase volume area ratios in the raceway wall surfaces first increased and then decreased, the
                 average temperature of the inner ring initially decreased and then significantly increased, while that of the outer ring
                 showed minimal change. These findings provided a basis for reducing the temperature rise in high-speed ball bearings
                 with under-race lubrication from the perspectives of oil supply parameter selection and cage structure parameter design.
                 Key words: high-speed ball bearings; under-race lubrication; thermal characteristic; rolling element rotation; cage


                航空发动机作为飞航武器装备的心脏,其推重比                          环下润滑角接触球轴承温升进行了研究,发现轴承温
            的提升对实现飞航武器装备的改进升级具有重要意                             升随转速的增加而增加. 朱卫兵等 发现相同工况下,
                                                                                             [4]
            义. 提高航空发动机推重比的重要措施是增加其主轴                           环下润滑的腔内油气分布比喷油润滑的分布更均匀,
            转速,而主轴转速的不断提升对其关键支承基础件—                            转速和载荷的增高使润滑效果下降,供油量的增加则
                                                                                         [5]
            滚动轴承的服役性能提出了挑战. 一方面,高速工况                           可以改善润滑效果. 王轶泽等 数值模拟计算多个位
            下轴承元件间的微滑动以及滚动体的自旋等运动特                             置处的温升,并通过加权平均得到轴承腔内最终温
            性变得显著,由此引起轴承的摩擦热量增大,温度增                            升,发现转速的增高使得轴承温升升高,供油量的增
              [1]
            高 ,使得轴承的润滑和摩擦状态变差,发生热失效的                           高使得总温升先显著降低后降低幅度趋于平缓. 但
            概率增加;另一方面,高速旋转的轴承内圈增大了由                            是,在以上学者的研究中均未考虑滚动体自转的影响.
                                                                    [6]
            环下孔供入轴承腔内油液的惯性,使得被甩出的油液                            Gao等 和Bao等    [7-8] 考虑了滚动体自转,研究了供油量
            体积增加,而进入到滚动体-套圈接触区域形成油膜                            和供油孔入口油速的影响,发现随着供油量或入口油
                                       [2]
            起到润滑作用的油液体积减少 ,轴承润滑和冷却效                            速的增加,轴承腔内平均油相体积分数有先增加后减
            果不佳,进一步增大了腔内温升,温升问题已成为限制                           小的趋势,存在最佳供油量和入口油速可以使更多的
                                                                                             [9]
            滚动轴承转速进一步提升的核心. 轴承的温升取决于其                          润滑油聚集在轴承空腔内. Jiang等 考虑了环下供油
            生热和传热情况,生热的来源为轴承内的摩擦热,而                            通道及多个供油孔,研究发现角接触球轴承腔内平均
            摩擦热的散发主要通过润滑剂的对流作用向外传递,                            油相体积分数随供油量成单调变化规律,这与Gao等                    [6]
            这与轴承腔内润滑剂的流动情况有关. 因此,有必要研                          和Bao等  [7-8] 提出的存在最佳供油量的结论相矛盾. 王
                                                                       [10]
            究高速滚动轴承在环下润滑方式下的热特性,分析影                            赵蕊佳等 在采用整体法计算生热量的基础上,建立
            响轴承温升的关键因素,为其热失效的解决提供依据.                           了未考虑滚动体自转和考虑滚动体自转的轴承流体
                在轴承热特性的常用分析方法中,有限体积法因                          域模型,对比发现滚动体自转使得轴承内部油液体积

            可同时考虑轴承元件的旋转运动和腔内两相润滑剂                             分数增大,也使得滑油穿透间隙到达外圈的能力增
            的流动对系统传热的影响,成为轴承热特性分析的常                            加,但作者所建立的滚动体自转模型仅为包含1个滚
            用方法. 采用这一方法,借助计算流体力学CFD (Com-                      动体和1个环下供油孔的周期模型,无法考虑润滑油
                                                                                               [11]
            putational fluid dynamics)仿真软件,大量学者们研究             在整个轴承腔内的流动情况. 翟强等 建立了角接触
            了不同工况和轴承结构参数对轴承热特性的影响. 李                           球轴承腔内流动模型,考虑了滚动体的自转,分析了
                  [3]
            小萍等 在使用局部法获得轴承总生热量的基础上对                            轴承换热效率和腔内流体的压力场分布,发现自转使
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