A Study on Friction of Journal Bearing under Dynamic Load

动载荷作用下轴颈轴承摩擦力的研究

• 批准号: 60460095
• 负责人: SOMEYA Tsuneo
• 金额: $ 4.8万
• 依托单位: The University of Tokyo
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (B)
• 财政年份: 1985
• 资助国家: 日本
• 起止时间: 1985 至 1987
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-60460095/
• 关键词: Internal Combustion Engine; Lubrication; Friction; Journal Bearing; Dynamic Load; 負圧発生

1. Objective: Journal bearings are usually used in multi-cylinder internal combustion engines. They are operating under very heavy dynamic load. On the other hand, their frictional loss should be low. Few studies have been presented which had dealt with pressure distribution, that is most important quantity for discussing all of bearing characteristics, under dynamic loading. Patrick had only measured simultaneously the frictional force in them. On this background, this study was carried out in order to make clear the dynamic characteristics of journal bearings.2. Approach: The test rig was designed and constructed so that all of basic and important quantity of journal bearing, namely pressure distribution, load of bearing, journal center orbit, oil temperature, frictional torque and oil flow rate, are simultaneously detectable. Data processing was carried out by on-line mini-computer system.Experimentally negative pressure was always measured. The maximum value is -0.35MPag. The liquid-gas two phase hydrodynamic lubrication theory was used to expound those negative pressure. Comparison was made between theoretical results and experimental one on pressure distribution, frictional torque and pil flow rate.3. Conclusings: (1) The shape of negative pressure distribution depends upon the loading pattern. The level of flat pressure region corresponding to oil film ruptured region is about absolute vacuum under high frequency of load. (2) The two-phase theory can explain negative pressure measured experimentally. However, it over-estimates value on the frictional torque. So, the theory should be improved from this point of view. (3) Measured values of frictional loss agreed qualitatively with theoretical results under static loading, whereas no reliable results were obtained under dynamic conditions by means of an imperfection of the measuring system. (4) Good agreement was obtained between the theoretical and the experimental results for oil flow.

1.目的：滑动轴承通常用于多缸内燃机。它们在非常重的动态负载下运行。另一方面，它们的摩擦损失应该很低。在动载荷下，压力分布是讨论所有轴承特性的最重要的量，但很少有研究涉及压力分布。帕特里克只是同时测量了它们之间的摩擦力。在此背景下，本文开展了滑动轴承的动力学特性研究.方法：该试验台的设计和建造，使所有的基本和重要的量的径向轴承，即压力分布，轴承的负载，轴颈中心轨道，油温，摩擦扭矩和油流量，是同时检测。数据处理采用微型计算机在线处理系统，并进行了负压测量实验。最大值为-0.35MPag。利用气液两相流体动压润滑理论对负压进行了解释。对压力分布、摩擦力矩和回流流量的理论计算结果与实验结果进行了比较.结论：（1）负压分布的形状取决于加载方式。在高频载荷下，油膜破裂区对应的平压区水平接近于绝对真空。(2)两相流理论可以解释实验测得的负压。然而，它高估了摩擦扭矩的值。因此，从这一角度出发，理论还有待进一步完善。(3)在静态载荷下，摩擦损失的测量值与理论结果定性一致，而在动态条件下，通过测量系统的不完善，没有得到可靠的结果。(4)油流的理论计算结果与实验结果吻合较好。