The integrity and reliability of a rotor depend significantly on the dynamic characteristics of its bearings. Bearing design has evolved in many ways in order to achieve higher damping and stiffness. A promising field in terms of vibrations control and overall performance improvement for the journal bearings is the use of smart lubricants. Smart lubricants are fluids with controllable properties. A suitable excitation, such as an electric or a magnetic field, is applied to the lubricant volume and changes its properties. Magnetorheological (MR) fluids consist one category of lubricants with controllable properties. Magnetic particles inside the MR fluid volume are coerced by a magnetic field. These particles form chains which hinder the flow of the base fluid and alter its apparent viscosity. According to the magnetic particle size, there are two subcategories of magnetorheological fluids: the regular MR fluids with particles sizing some tens of micrometers and the nanomagnetorheological (NMR) fluids with a particle size of a few nanometers. The change of magnetorheological fluid's viscosity is an efficient way of control of the dynamic characteristics of the journal bearing system. In this work, the magnetic field intensity inside the volume of lubricant is calculated through finite element analysis. The calculated value of the magnetic field intensity is used to define the apparent viscosity of both the MR and the NMR fluids. Using computational fluid dynamics (CFD) method, the pressure developed inside the journal bearing is found. Through this simulation with the use of a suitable algorithm, the stiffness and damping coefficients are calculated and stability charts of Newtonian, MR, and NMR fluid are presented and discussed.

References

References
1.
Hung
,
N. Q.
, and
Bok
,
C. S.
,
2012
, “
Optimal Design of a T-Shaped Drum-Type Brake for Motorcycle Utilizing Magnetorheological Fluid
,”
Mech. Based Des. Struct. Mach.
,
40
(
2
), pp.
153
162
.10.1080/15397734.2011.616479
2.
Wang
,
D.
, and
Liao
,
W.
,
2011
, “
Magnetorheological Fluid Dampers: A Review of Parametric Modelling
,”
Smart Mater. Struct.
,
20
(
2
), p.
023001
.10.1088/0964-1726/20/2/023001
3.
Wiltsie
,
N.
,
Lanzetta
,
M.
, and
Iagnemma
,
K.
,
2012
, “
A Controllably Adhesive Climbing Robot Using Magnetorheological Fluid
,”
2012 IEEE International Conference on Technologies for Practical Robot Applications (TePRA)
, Woburn, MA, Apr. 23–24, IEEE, pp.
91
96
.
4.
Hesselbach
,
J.
, and
Abel-Keilhack
,
C.
,
2003
, “
Active Hydrostatic Bearing With Magnetorheological Fluid
,”
J. Appl. Phys.
,
93
(
10
), pp.
8441
8443
.10.1063/1.1555850
5.
Šafařík
,
I.
,
Horská
,
K.
, and
Šafaříková
,
M.
,
2011
, “
Magnetic Nanoparticles for Biomedicine
,”
Intracellular Delivery
,
A.
Prokop
, ed.,
Springer
, Dordrecht
, The Netherlands
, pp.
363
372
.
6.
Fijalkowski
,
B.
,
2011
, “
A Novel Internal Combustion Engine Without Crankshaft and Connecting Rod Mechanisms
,”
J. Kones Powertrain Transp.
,
18
(
4
), pp.
91
104
.
7.
Zhang
,
H. H.
,
Xu
,
H. P.
,
Liao
,
C. R.
, and
Deng
,
Z. X.
,
2012
, “
Dynamic Response of Magnetorheological Fluid Damper for Automotive Suspension and the Influence by Long-Time Standing-Still
,”
Appl. Mech. Mater.
,
105
, pp.
1689
1692
.10.4028/www.scientific.net/AMM.105-107.1689
8.
Chaudhuri
,
A.
,
Wang
,
G.
,
Wereley
,
N.
,
Tasovksi
,
V.
, and
Radhakrishnan
,
R.
,
2005
, “
Substitution of Micron by Nanometer Scale Powders in Magnetorheological Fluids
,”
Int. J. Mod. Phys. B
,
19
(
07n09
), pp.
1374
1380
.10.1142/S0217979205030323
9.
Vékás
,
L.
,
2009
, “
Ferrofluids and Magnetorheological Fluids
,”
Adv. Sci. Technol.
,
54
, pp.
127
136
.10.4028/www.scientific.net/AST.54.127
10.
Kim
,
I.
,
Song
,
K.
,
Park
,
B.
,
Choi
,
B.
, and
Choi
,
H. J.
,
2011
, “
Nano-Sized Fe Soft-Magnetic Particle and Its Magnetorheology
,”
Colloid Polym. Sci.
,
289
(
1
), pp.
79
83
.10.1007/s00396-010-2322-7
11.
Lopez-Lopez
,
M.
,
Bossis
,
G.
,
Duran
,
J.
,
Gomez-Ramirez
,
A.
,
Kuzhir
,
P.
,
Iskakova
,
L.
, and
Zubarev
,
Y. A.
,
2013
, “
Inversion of Magnetic Forces Between Microparticles and Its Effect on the Magnetorheology of Extremely Bidisperse Magnetic Fluids
,”
J. Nanofluids
,
2
(
2
), pp.
85
93
.10.1166/jon.2013.1049
12.
Shafrir
,
S. N.
,
Romanofsky
,
H. J.
,
Skarlinski
,
M.
,
Wang
,
M.
,
Miao
,
C.
,
Salzman
,
S.
,
Chartier
,
T.
,
Mici
,
J.
,
Lambropoulos
,
J. C.
, and
Shen
,
R.
,
2009
, “
Zirconia-Coated Carbonyl-Iron-Particle-Based Magnetorheological Fluid for Polishing Optical Glasses and Ceramics
,”
Appl. Opt.
,
48
(
35
), pp.
6797
6810
.10.1364/AO.48.006797
13.
Li
,
Q.
,
Yu
,
G.
,
Liu
,
S.
, and
Zheng
,
S.
,
2012
, “
Application of Computational Fluid Dynamics and Fluid Structure Interaction Techniques for Calculating the 3D Transient Flow of Journal Bearings Coupled With Rotor Systems
,”
Chin. J. Mech. Eng.
,
25
(
5
), pp.
926
932
.10.3901/CJME.2012.05.926
14.
Chouksey
,
M.
,
Dutt
,
J. K.
, and
Modak
,
S. V.
,
2012
, “
Modal Analysis of Rotor-Shaft System Under the Influence of Rotor-Shaft Material Damping and Fluid Film Forces
,”
Mech. Mach. Theory
,
48
, pp.
81
93
.10.1016/j.mechmachtheory.2011.09.001
15.
San Andrés
,
L.
,
2012
, “
Extended Finite Element Analysis of Journal Bearing Dynamic Forced Performance to Include Fluid Inertia Force Coefficients
,”
ASME
Paper No. IMECE2012-87713. 10.1115/IMECE2012-87713
16.
Kirk
,
R.
,
Alsaeed
,
A.
, and
Gunter
,
E.
,
2007
, “
Stability Analysis of a High-Speed Automotive Turbocharger
,”
Tribol. Trans.
,
50
(
3
), pp.
427
434
.10.1080/10402000701476908
17.
Forte
,
P.
,
Paterno
,
M.
, and
Rustighi
,
E.
,
2004
, “
A Magnetorheological Fluid Damper for Rotor Applications
,”
Int. J. Rotating Mach.
,
10
(
3
), pp.
175
182
.10.1155/S1023621X04000181
18.
Urreta
,
H.
,
Leicht
,
Z.
,
Sanchez
,
A.
,
Agirre
,
A.
,
Kuzhir
,
P.
, and
Magnac
,
G.
,
2010
, “
Hydrodynamic Bearing Lubricated With Magnetic Fluids
,”
J. Intell. Mater. Syst. Struct.
,
21
(
15
), pp.
1491
1499
.10.1177/1045389X09356007
19.
Schultz
,
W. W.
,
Han
,
H.-C.
,
Boyd
,
J. P.
, and
Schumack
,
M.
,
1997
, “
An Analysis of the Oil-Whirl Instability
,”
Proceedings of the APS Division of Fluid Dynamics Meeting Abstracts
.
20.
Tichy
,
J. A.
,
1991
, “
Hydrodynamic Lubrication Theory for the Bingham Plastic Flow Model
,”
J. Rheol.
,
35
(
4
), pp.
477
496
.10.1122/1.550231
22.
Gunter
,
E. J.
,
2003
, “
Lund's Contribution to Rotor Stability: The Indispensable and Fundamental Basis of Modern Compressor Design
,”
ASME J. Vib. Acoust.
,
125
(
4
), pp.
462
470
.10.1115/1.1605978
23.
Gertzos
,
K.
,
Nikolakopoulos
,
P.
, and
Papadopoulos
,
C.
,
2008
, “
CFD Analysis of Journal Bearing Hydrodynamic Lubrication by Bingham Lubricant
,”
Tribol. Int.
,
41
(
12
), pp.
1190
1204
.10.1016/j.triboint.2008.03.002
24.
Odenbach
,
S.
,
2009
,
Colloidal Magnetic Fluids: Basics, Development and Application of Ferrofluids
,
Springer
, Dordrecht, The Netherlands.
25.
Glienicke
,
J.
,
Han
,
D. C.
, and
Leonhard
,
M.
,
1980
, “
Practical Determination and Use of Bearing Dynamic Coefficients
,”
Tribol. Int.
,
13
(
6
), pp.
297
309
.10.1016/0301-679X(80)90094-8
26.
Shenoy
,
S. B.
,
Pai
,
R.
,
Rao
,
D.
, and
Pai
,
R. B.
,
2009
, “
Elasto-Hydrodynamic Lubrication Analysis of Full 360 Journal Bearing Using CFD and FSI Techniques
,”
World J. Model. Simul.
,
5
(
4
), pp.
315
320
.
27.
Bompos
,
D. A.
, and
Nikolakopoulos
,
P. G.
,
2011
, “
CFD Simulation of Magnetorheological Fluid Journal Bearings
,”
Simul. Modell. Pract. Theory
,
19
(
4
), pp.
1035
1060
.10.1016/j.simpat.2011.01.001
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