Effect of Deterministic Asperity Geometry on Hydrodynamic Lubrication
Author:
Siripuram Ravinder B.1, Stephens Lyndon S.1
Affiliation:
1. Bearings and Seals Laboratory, Department of Mechanical Engineering, University of Kentucky, 151 Ralph G. Anderson Building, Lexington, KY 40506-0503
Abstract
This paper presents a numerical study of the effects of different shapes of deterministic microasperities in sliding surface lubrication when hydrodynamic films are found. Positive (protruding) and negative (recessed) asperities of constant height (depth) are considered with circular, square, diamond, hexagonal and triangular cross-sections. Of particular interest is the impact of asperity/cavity cross-sectional geometry on friction and leakage, which has importance in sealing applications. The results indicate that the friction coefficient is insensitive to asperity/cavity shape, but quite sensitive to the size of the cross-section. By contrast, leakage rates are found to be quite sensitive to both cross-sectional shape and size, with triangular asperities giving the smallest leakage rate and square asperities giving a largest leakage rate. The minimum coefficient of friction for all shapes is found to occur at an asperity area fraction of 0.2 for positive asperities and 0.7 for negative asperities. Finally, the results indicate the existence of a critical asperity area fraction where the performance curves for positive and negative asperities cross over. These cross-over points are identified for friction coefficient and leakage rate.
Publisher
ASME International
Subject
Surfaces, Coatings and Films,Surfaces and Interfaces,Mechanical Engineering,Mechanics of Materials
Reference14 articles.
1. Anno, J. N., Walowit, J. A., and Allen, C. M., 1969, “Load Support and Leakage From Microasperity-Lubricated Face Seals,” ASME J. Lubr. Technol., pp. 726–731. 2. Etsion, I., Halperin, G., and Ryk, G., 2000, “Improving Tribological Performance of Mechanical Components by Laser Surface Texturing,” Journal of the Balkan Tribological Association, 6(2), pp. 72–77. 3. Stephens, L. S., Siripuram, R., Hayden, M., and McCartt, B., 2002, “Deterministic Microasperities on Bearings and Seals Using a Modified LIGA Process,” Proceedings of ASME Turbo Expo 2002, Paper No. GT-2002-30289. 4. Kortikar, S. N., Stephens, L. S., Hadinata, P. C., and Siripuram, R. B., 2003, “Manufacturing of Microasperities on Thrust Surfaces Using Ultraviolet Photolithography,” Proceedings of the ASPE 2003 Winter Topical Meeting, 28, pp. 148–153. 5. Becker, E. W., Ehrfeld, W., Hagmann, P., Maner, A., and Munchmeyer, D., 1986, “Fabrication of Microstructures With Extreme Structural Heights by Synchrotron Radiation Lithography, Galvanoforming and Plastic Moulding (LIGA Process),” Microelectron. Eng., 4, pp. 35–56.
Cited by
155 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献
|
|