The complicated motion of the journal in an unlubricated bearing in response to an applied torque is analyzed. The theory identifies the conditions for various distinct modes of motion to occur, including the “dry friction whirl” cited in the literature. The crucial dependence of the motion on the friction coefficient and the normal and tangential restitution coefficients, as revealed by the theory, suggest that perhaps these latter parameters of motion can be determined by measuring the journal’s motion in an unlubricated journal bearing.

Issue Section:
Research Papers
Topics:
Journal bearings, Bearings, Dry friction, Friction, Torque, Whirls
1.
Ehrich
F. F.
,
1969
, “
The Dynamic Stability of Rotor/Stator Radial Rubs in Rotating Machinery
,”
ASME Journal of Engineering for Industry
, Vol.
91
, pp.
1025
–
1028
.
2.
Foerster
S. F.
,
Louge
M. Y.
,
Chang
Hongder
, and
Allia
Khedidja
,
1994
, “
Measurements of the Collision Properties of Small Spheres
,”
Physics of Fluids
, Vol.
6
, pp.
1108
–
1115
.
3.
Press, W. H., et al., 1986, Numerical Recipes, Cambridge University Press, pp. 550–554.
4.
Sapetta, L. P., and Harker, R. J., 1967, “Whirl of Power Screws Excited by Boundary Lubrication at the Interface,” ASME Paper 67-Vibr-37.
5.
Shaw, M. C., and Macks, E. F., 1949, Analysis and Lubrication of Bearings, McGraw-Hill, pp. 367–369.
6.
Xu, Jing, 1995, “A Study of the Starting Characteristics of an Unlubricated Journal Bearing,” Master’s thesis, State University of New York at Binghamton.
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