A fast and accurate model to calculate the fluid-film forces of a fluid-film bearing with the Reynolds boundary condition is presented in the paper by using the free boundary theory and the variational method. The model is applied to the nonlinear dynamical behavior analysis of a rigid rotor in the elliptical bearing support. Both balanced and unbalanced rotors are taken into consideration. Numerical simulations show that the balanced rotor undergoes a supercritical Hopf bifurcation as the rotor spin speed increases. The investigation of the unbalanced rotor indicates that the motion can be a synchronous motion, subharmonic motion, quasi-period motion, or chaotic motion at different rotor spin speeds. These nonlinear phenomena are investigated in detail. Poincaré maps, bifurcation diagram and frequency spectra are utilized as diagnostic tools.

1.
Holmes
,
A. G.
,
Ettles
,
C. M.
, and
Mayes
,
I. W.
, 1978, “
Aperiodic Behaviour of a Rigid Shaft in Short Journal Bearings
,”
Int. J. Numer. Methods Eng.
0029-5981,
12
, pp.
695
702
.
2.
Bently
,
D. E.
, 1974, “
Forced Subrotative Speed Dynamic Action of Rotating Machinery
,” ASME Paper No. 74-PET-16.
3.
Ehrich
,
F. F.
, 1966, “
Subharmonic Vibration of Rotors in Bearing Clearance
,” ASME Paper No. 66-MD-1.
4.
Ehrich
,
F. F.
, 1988, “
High Order Subharmonic Response of High Speed Rotor in Bearing Clearance
,”
ASME J. Vib., Acoust., Stress, Reliab. Des.
0739-3717,
110
, pp.
695
702
.
5.
Ehrich
,
F. F.
, 1991, “
Some Observations of Chaotic Vibration Phenomena in High-Speed Rotor Dynamics
,”
ASME J. Vibr. Acoust.
0739-3717,
113
, pp.
50
57
.
6.
Lund
,
J. W.
, 1987, “
Review of the Concept of Dynamic Coefficients for Fluid Film Journal Bearings
,”
ASME J. Tribol.
0742-4787,
109
, pp.
38
41
.
7.
Zheng
,
T.
, and
Hasebe
,
N.
, 2000, “
Nonlinear Dynamic Behaviors of a Complex Rotor-Bearing System
,”
ASME J. Appl. Mech.
0021-8936,
67
, pp.
485
495
.
8.
Zheng
,
T.
, and
Hasebe
,
N.
, 2000, “
Calculation of Equilibrium Position and Dynamic Coefficients of a Journal Bearing Using Free Boundary Theory
,”
ASME J. Tribol.
0742-4787,
122
, pp.
616
621
.
9.
Jang
,
G. H.
, and
Yoon
,
J. W.
, 2002, “
Nonlinear Dynamic Analysis of a Hydrodynamic Journal Bearing Considering the Effect of a Rotating or Stationary Herringbone Groove
,”
ASME J. Tribol.
0742-4787,
124
, pp.
297
304
.
10.
Mehta
,
N. P.
,
Rattan
,
S. S.
, and
Gian
,
B.
, 2003, “
Static and Dynamic Characteristics of Four-Lobe Pressure-Dam Bearings
,”
Tribol. Lett.
1023-8883,
15
(
4
), pp.
415
420
.
11.
Sharma
,
S. C.
,
Kumar
,
V.
,
Jain
,
S. C.
,
Sinhasan
,
R.
, and
Subramanian
,
M.
, 1999, “
A Study of Slot-Entry Hydrostatic/Hybrid Journal Bearing Using the Finite Element Method
,”
Tribol. Int.
0301-679X,
32
, pp.
185
196
.
12.
Rho
,
B. H.
, and
Kim
,
K. W.
, 2002, “
A Study of the Dynamic Characteristics of Synchronously Controlled Hydrodynamic Journal Bearings
,”
Tribol. Int.
0301-679X,
35
, pp.
339
345
.
13.
Rho
,
B. H.
, and
Kim
,
K. W.
, 2003, “
Acoustical Properties of Hydrodynamic Journal Bearings
,”
Tribol. Int.
0301-679X,
36
, pp.
61
66
.
14.
Someya
,
T.
, 1988,
Journal-Bearing Databook
,
Spinger-Verlag
,
Berlin, Germany
.
15.
Yang
,
B. S.
,
Lee
,
Y. H.
,
Choi
,
B. K.
, and
Kim
,
B. K.
, 2001, “
Optimum Design of Short Journal Bearings by Artificial Life Algorithm
,”
Tribol. Int.
0301-679X,
34
(
7
), pp.
427
435
.
16.
Rohde
,
S. M
, and
Li
,
D. F.
, 1980, “
A Generalized Short Bearing Theory
,”
ASME J. Lubr. Technol.
0022-2305,
102
, pp.
278
282
.
17.
Vance
,
J. M.
, 1988,
Rotordynamics of Turbomachinery
,
Wiley
,
New York
.
18.
Trumpler
,
P. R.
, 1966,
Design of Film Bearings
,
Macmillan
,
New York
.
19.
Brown
,
R. D.
,
Addison
,
P.
, and
Chan
,
A. H. C.
, 1994, “
Chaos in the Unbalance Response of Journal Bearings
,”
Nonlinear Dyn.
0924-090X,
5
, pp.
421
432
.
20.
Capone
,
G.
, and
Russo
,
M.
, 1990, “
Short Bearing Theory Prediction of Inertial Turbulent Journal Orbits
,”
ASME J. Tribol.
0742-4787,
112
, pp.
643
649
.
21.
Hollis
,
P.
, and
Taylor
,
D. L.
, 1986, “
Hopf Bifurcation to Limit Cycles in Fluid Film Bearings
,”
Trans. ASME, J. Tribol.
0742-4787,
108
(
2
), pp.
184
189
.
22.
Inayat-Hussain
,
J. I.
,
Kanki
,
H.
, and
Mureithi
,
N. W.
, 2003, “
On the Bifurcation of a Rigid Rotor Response in Squeeze-Film Dampers
,”
J. Fluids Struct.
0889-9746,
17
, pp.
433
459
.
23.
Myers
,
C. J.
, 1984, “
Bifurcation Theory Applied to Oil Whirl in Plain Cylindrical Journal Bearings
,”
ASME J. Appl. Mech.
0021-8936,
51
, pp.
244
250
.
24.
Rohde
,
S. M.
, and
Mallister
,
G. T.
, 1975, “
A Variational Formulation for a Class of Free Boundary Problems Arising in Hydrodynamic Lubrication
,”
Int. J. Eng. Sci.
0020-7225,
13
, pp.
841
850
.
25.
Barrett
,
L. E.
,
Akers
,
A.
, and
Gunter
,
E. J.
, 1976, “
Effect of Unbalance on a Journal Bearing Undergoing Oil Whirl
,”
Proc. Inst. Mech. Eng.
0020-3483,
190
, pp.
525
543
.
26.
Seydel
,
R.
, 1988,
From Equilibrium to Chaos, Practical Bifurcation and Stability Analysis
,
Elsevier
,
New York
.
You do not currently have access to this content.