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Updated: Jun 28, 2026
09:21
Experiments on Ultrasonic Lubrication Using a Piezoelectrically-assisted Tribometer and Optical Profilometer
Published on: September 28, 2015
Studies on tribology.
1Kanazawa Institute of Technology, Tokyo, Japan.
Summary
This study investigates oil whip vibrations in rotating machinery, explaining their cause in journal bearings and proposing preventive methods. It also explores novel lubrication techniques like water and gas lubrication for improved machine performance.
Area of Science:
- Mechanical Engineering
- Tribology
- Fluid Dynamics
Background:
- High-speed rotating machines like turbines and generators are susceptible to shaft vibrations, potentially leading to operational issues or failure.
- Oil whip, a vibration phenomenon caused by oil film action in journal bearings, significantly impacts machine stability.
- Understanding lubrication dynamics is crucial for mitigating these vibrations and ensuring machine longevity.
Purpose of the Study:
- To elucidate the mechanism of oil whip vibrations in journal bearings and propose effective preventive strategies.
- To analyze heat generation and temperature rise in hydrodynamic lubrication under various conditions.
- To explore and evaluate novel lubrication methods, including water, nitrogen gas, and tribo-coated indium lubrication, for high-speed rotating machinery.
Main Methods:
- Theoretical and experimental analyses of hydrodynamic lubrication, focusing on heat generation and temperature rise.
- Application of k-epsilon lubrication theory to analyze bearings with high eccentricity ratios.
- Investigation into the mechanisms of water, nitrogen gas, and tribo-coated indium lubrication, including tribo-layer formation and wear.
Main Results:
- The study explains the mechanism of oil whip and presents a preventive method.
- Theoretical and experimental analyses confirm the importance of considering heat generation and temperature rise in hydrodynamic lubrication.
- The k-epsilon model proves useful for bearings with high eccentricity ratios.
- Novel lubrication methods demonstrate promise, with the importance of the tribo-layer highlighted.
- Mechanisms of static friction generation in both plastic and elastic contact are elucidated.
Conclusions:
- Oil whip is a critical vibration issue in rotating machinery, manageable through proposed preventive methods.
- Advanced lubrication theories and techniques, such as the k-epsilon model and novel lubrication methods, are essential for optimizing performance and preventing failures.
- Understanding tribology, including tribo-layer formation and static friction, is fundamental to advancing lubrication science and machine reliability.
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