Application of Theory of Super Lubricity of Minimum Entropy Welding

最小熵焊接超润滑理论的应用

• 批准号: 11650148
• 负责人: NAKANO Takashi
• 金额: $ 2.24万
• 依托单位: TOKYO INSTITUTE OF TECHNOLOGY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1999
• 资助国家: 日本
• 起止时间: 1999 至 2000
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-11650148/
• 关键词: Flagellar Motor; Hydrodynamic lubrication; Molecular Force; Electric Double Layer; PL ring; Super Lubricity; Wavelet; Microtribology; Mot A

From the viewpoint of mechanical engineering, the bacterial flagellar motor has several interesting features ; it rotates at a maximum speed of 17,000 HZ, and the diameter of the rotor is about 50 nm. In nature, the driving system using rotational motion is found only in single-celled organisms bacteria, while beating motion dominates the non-bacterial world.Since life chooses the more efficient mechanism in the process of evolution, it is interesting to know the reasons why bacteria chose rotational motion rather than beating motion.On the other hand, motors are widely used as driving systems in engineering. When we consider the difficulty of lubrication in microtribology which occurs in a world as small as bacteria, knowledge about the f1agellar motor will be useful to solve the problems.In the 20th century, tribology and lubrication engineering on the macroscale have reached a paradigm that most of the solid frictions in engineering can be well described by Coulomb-Amonton's law and … More that the best strategy of lubrication is fluid film lubrication. Here, deviations from Coulomb's law such as the friction of rubber or super-lubricity are considered to be exceptional cases.Now, entering the 21st century, the circumstances around tribology are drastically changing. Since the paradigm is not always applicable to newly emerging areas such as microtribology, we have to employ some other paradigms for friction and lubrication.In microtribology, friction between ideal crystalline surfaces may sometimes occur. Molecular forces would play an essential role in this kind of friction. Therefore, Coulomb's law is not powerful anymore ; as it is an experimental rule for solid friction. Molecular forces affect the behavior of liquids in molecularly thin liquid films. When thin film viscosity (or a viscosity rise) is duced by molecular forces, the fluid film lubrication method will not be the best anymore. Until now, we have not obtained enough knowledge about the lubrication in micromachines.In the flagellar motor of some bacterial species, there is a bushing, called the PL ring, which allows the rotating shaft to penetrate the rigid cell wall. The existence of the PL ring suggests that our classical method of lubrication might be still valid in microtribology. In a recent study, we calculated parameters in the tribology of the PL ring using theory of the classical hydrodynamic lubrication and the parameter values in thin film viscosity. The results showed that the friction values thus calculated are too high to operate the motor at high speeds, indicating invalidity of the classical method.In this study, we show that the ordinary theory for hydrodynamic lubrication is not an adequate tool for analysis of lubrication in the PL ring. We also calculate the scale invariance of the Stokes equation and consider other possible lubrication mechanisms. Less

从机械工程的角度来看，细菌鞭毛马达有几个有趣的特征;它以17，000 HZ的最大速度旋转，转子的直径约为50 nm。在自然界中，利用旋转运动的驱动系统只存在于单细胞生物细菌中，而在非细菌世界中，跳动运动占主导地位。由于生命在进化过程中选择了更有效的机制，因此了解细菌选择旋转运动而不是跳动运动的原因是有趣的。另一方面，电机在工程中被广泛用作驱动系统。微摩擦学中的润滑问题是一个小如细菌的世界所面临的难题，而摩擦马达的知识将有助于解决这一问题。世纪，宏观尺度上的摩擦学和润滑工程已达到一种范式，即工程中的固体摩擦大多数可以用库仑-阿蒙顿定律来描述，而摩擦学中的摩擦学和润滑工程则可以用库仑-阿蒙顿定律来描述。 ...更多信息 最佳的润滑策略是液膜润滑。在这里，橡胶的摩擦或超润滑性等偏离库仑定律的情况被认为是例外。进入世纪，摩擦学的环境正在发生巨大的变化。由于该范式并不总是适用于新兴的领域，如微摩擦学，我们不得不采用其他范式的摩擦和润滑。分子力在这种摩擦中起着至关重要的作用。因此，库仑定律不再有效，因为它是固体摩擦的实验规则。分子力影响液体在分子薄液膜中的行为。当分子力引起薄膜粘度（或粘度上升）时，液膜润滑方法将不再是最好的。到目前为止，我们对微机械中的润滑还没有得到足够的了解。在一些细菌物种的鞭毛马达中，有一个衬套，称为PL环，它允许旋转轴穿透刚性细胞壁。PL环的存在表明我们的经典润滑方法在微摩擦学中可能仍然有效。在最近的一项研究中，我们使用经典流体动力润滑理论和薄膜粘度的参数值计算PL环的摩擦学参数。结果表明，这样计算的摩擦值太高，在高速运行的电动机，表明无效的经典method.In这项研究中，我们表明，普通的流体动力润滑理论是不是一个足够的工具，在PL环的润滑分析。我们还计算了斯托克斯方程的尺度不变性，并考虑了其他可能的润滑机制。少

项目成果

中野隆 他2名: "バクテリアべん毛モータの潤滑における非流体力学的効果の解析"トライボロジー会議予稿集. 2000・5. 138-139 (2000)

Takashi Nakano 等 2 人：“细菌鞭毛马达润滑中的非流体动力效应分析”摩擦学会议论文集 2000・5（2000 年）。

中野隆: "バクテリアべん毛モータの潤滑における非流体力学的効果の解析"トライボロジー会議予稿集 東京. 2000・5. 249-250 (2000)

Takashi Nakano：“细菌鞭毛马达润滑中的非流体动力效应分析”摩擦学会议论文集2000・5（2000）。

中野隆 他2名: "べん毛を有するバクテリアの推進機構に関するトライボロジ解析"トライボロジー会議予稿集. 1999・5. 99-100 (1999)

Takashi Nakano 等 2 人：“鞭毛细菌推进机制的摩擦学分析”摩擦学会议记录 1999・5（1999）。

Takashi NAKANO: "Wavelet Analysis of Non-uniform Surface Profile"Proceedings of JAST Tribology Conference Takamatsu. 1999-10. 1-2 (1999)

Takashi NAKANO：“非均匀表面轮廓的小波分析”高松 JAST 摩擦学会议论文集。

Takashi NAKANO, Satoshi MOMOZONO, Shin-ich AIZAWA: "Tribologiacal Analysis of Bactrial Flagellar Motor"Synopsis of International Tribology Conference NAFGASAKI 2000. 292-292 (2000)

Takashi NAKANO、Satoshi MOMOZONO、Shin-ich AIZAWA：“细菌鞭毛运动的摩擦学分析”国际摩擦学会议 NAFGASAKI 2000 年概要。292-292 (2000)