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Effects of Couple Stresses on Pure Squeeze EHL Motion of Circular Contacts

Published online by Cambridge University Press:  05 May 2011

H.-M. Chu ,
W.-L. Li  and
S. Y. Hu
H.-M. Chu*
Affiliation:
Department of Mechanical Engineering, Yung-Ta Institute of Technology & Commerce, Ping-Tung, Taiwan 909, R.O.C.
W.-L. Li*
Affiliation:
Department of Mechanical Engineering, National Kaohsiung University of Applied Sciences, Kaohsiung, Taiwan 807, R.O.C.
S. Y. Hu*
Affiliation:
Department of Marine Engineering, National Kaohsiung Marine University, Kaohsiung, Taiwan 811, R.O.C.
*
*Assistant Professor
**Professor
***Associate Professor
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Abstract

A method for investigating the pure squeeze action in an isothermal elastohydrodynamically lubrication (EHL) problem, i.e., circular contacts lubricated with couple stress fluid, was developed. A constant load condition was used in the calculations. The initial conditions such as pressure profiles, normal squeeze velocities, and film shapes were obtained from the classical hydrodynamic lubrication theory at a specified large central film thickness. The coupled transient modified Reynolds, elasticity deformation, and load equilibrium equations are solved simultaneously. The simulation results reveal that the effect of the couple stress is equivalent to enhancing the lubricant viscosity, thus enlarging the film thickness. The effect of couple stress in thin film lubrication varies with film size. That is, the thinner the lubricating film is, the more obvious the effect of couple stress is. For larger characteristic length, materials parameter, and load, the central pressure, central film thickness, and rigid separation are larger than those of smaller characteristic length under the same load. The time needed to achieve maximum central pressure and the Hertzian pressure increases with increasing characteristic length.

Keywords

EHLSqueeze filmCouple stress fluidsMicrocontinuum theory.
Type
Technical Note
Information
Journal of Mechanics , Volume 22 , Issue 1 , March 2006 , pp. 77 - 84
Copyright
Copyright © The Society of Theoretical and Applied Mechanics, R.O.C. 2006

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References

REFERENCES

1.Christensen, H., “The Oil Film in a Closing Gap”, Proc. R. Soc. London, Series A, 226, pp. 312–328 (1962).Google Scholar
2.Lee, K. M. and Cheng, H. S., “The Pressure and Deformation Profiles Between Two Normally Approaching Lubricated Cylinders,” ASME, J. Lubr. Technol, 95(3), pp. 308–317 (1973).CrossRefGoogle Scholar
3.Safa, M. M. A. and Gohar, R., “Pressure Distribution Under a Ball Impacting a Thin Lubricant Layer,” ASME, J. of Tribology, 108, pp. 372–376 (1986).CrossRefGoogle Scholar
4.Yang, P. R. and Wen, S. Z., “Pure Squeeze Action in an Isothermal Elastohydrodynamic Lubricated Spherical Conjunction, Part 1: Theory and Dynamic Load Results,” Wear, 142, pp. 1–16 (1991).CrossRefGoogle Scholar
5.Yang, P. R. and Wen, S. Z., “Pure Squeeze Action in an Isothermal Elastohydrodynamic Lubricated Spherical Conjunction, Part 2: Constant Speed and Constant Load Results,” Wear, 142, pp. 17–30 (1991).CrossRefGoogle Scholar
6.Dowson, D. and Wang, D., “An Analysis of the Normal Bouncing of a Solid Elastic Ball on an Oily Plate,” Wear, 179, pp. 29–37 (1994).CrossRefGoogle Scholar
7.Larsson, R. and Höglund, E., “Elastohydrodynamic Lubricated at Pure Squeeze Action,” Wear, 179, pp. 39–43 (1994).CrossRefGoogle Scholar
8.Larsson, R. and Höglund, E., “Numerical Simulation of a Ball Impacting and Rebounding a Lubricated Surface,” ASME, J. of Tribology, 117, pp. 94–102 (1995).CrossRefGoogle Scholar
9.Lee, R. T. and Hamrock, B. J., “Squeeze and Entraining Motion in Nonconformal Line Contacts, Part I: Hydrodynamic Lubrication,” ASME, J. of Tribology, 111, pp. 1–8 (1989).CrossRefGoogle Scholar
10.Lee, R. T. and Hamrock, B. J., “Squeeze and Entraining Motion in Nonconformal Line Contacts, Part II: Elastohy drodynamic Lubrication,” ASME, J. of Tribology, 111, pp. 8–16 (1989).CrossRefGoogle Scholar
11.Ariman, T. and Sylvester, N. D., “Microcontinuum Fluid Mechanics A. Review,” Int. J. Eng. Sci., 11, pp. 905–930 (1973).CrossRefGoogle Scholar
12.Ariman, T. and Sylvester, N. D., “Applications of Microcontinuum Fluid Mechanics,” Int. J. Eng. Sci., 12, pp. 273–293 (1974).CrossRefGoogle Scholar
13.Stokes, V. K., “Couple Stresses in Fluids,” Phys. Fluids, 9, pp. 1709–1715 (1966).CrossRefGoogle Scholar
14.Ramanaish, G., and Sarkar, P., “Squeeze Films and Thrust Bearings Lubricated by Fluids with Couple Stress,” Wear, 48, pp. 309–316 (1978).CrossRefGoogle Scholar
15.Ramanaish, G., “Squeeze Films Between Finite Plates Lubricated by Fluids with Couple Stress,” Wear, 54, pp. 315–320 (1979).CrossRefGoogle Scholar
16.Lin, J. R., “Squeeze Film Characteristics of Long Partial Journal Bearings Lubricated with Couple Stress Fluids,” Tribology International, 30, pp. 53–58 (1997).CrossRefGoogle Scholar
17.Mokhiamer, U. M., Crosby, W. A., and Ei-Gamal, H.A., “A Study of a Journal Bearing Lubricated by Fluids with Couple Stress Considering the Elasticity of the Liner,” Wear, 224, pp. 194–201 (1999).CrossRefGoogle Scholar
18.Naduvinamani, N. B., Hiremath, P. S., and Gurubasavaraj, G., “Squeeze Film Lubrication of a Short Porous Journal Bearing with Couple Stress Fluids,” Tribology International, 34, pp. 739–747 (2001).CrossRefGoogle Scholar
19.Lin, J. R., “Squeeze Film Characteristics Between a Sphere and a Flat Plate: Couple Stress Fluid Model,” Computers and Structures, 75, pp. 73–80 (2000).CrossRefGoogle Scholar
20.Roelands, C. J. A., Vlugter, J. C., and Watermann, H. L., “The Viscosity Temperature Pressure Relationship of Lubricating Oils and Its Correlation with Chemical Constitution,” ASME, Journal of Basic Engineering, pp. 601–606 (1963).CrossRefGoogle Scholar