A microstructural model of the motion of particle pairs in MR fluids is proposed that accounts for both hydrodynamic and magnetic field forces. A fluid constitutive equation is derived from the model that allows prediction of velocity and particle structure fields. Results for simple shear and elongational flows are presented for cases where particle pairs remain in close contact so they are hydrodynamically equivalent to an ellipsoid of aspect ratio two. Additionally, only the magnetic force component normal to the vector connecting the centers of a particle pair affects motion. Shear flow results indicate particle pairs rotate continuously with the flow at low magnetic fields while a steady state is reached at high fields. For elongational flows, when the applied magnetic field is parallel to the elongation direction, particle pairs orient in the field/flow direction. Either orientation is possible when the field is perpendicular to the flow.

1.
Gulley
G. L.
and
Tao
R.
,
2001
, “
Structures of a Magnetorheological Fluid
,”
Int. J. of Modern Physics B
,
15
(
6&7
), pp.
851
858
.
2.
Rosensweig
R. E.
,
1995
, “
On magnetorheology and electrorheology as states of unsymmetric stress
,”
J. of Rheology
,
39
(
1
), pp.
179
192
.
3.
http://www.magneshocks.com, 2005.
4.
Yang, G., 2001, “Large-Scale Magnetorheological Fluid Damper for Vibration Mitigation: Modeling, Testing and Control,” Ph.D. Thesis, University of Notre Dame, South Bend, IN.
5.
Carlson, J.D., 2001, “Magnetorheological Brake with Integrated Flywheel,” US Patent Number 6,186,290B1.
6.
Visnic, B., 2005, “Grip and Grin; Torque vectoring punches up all-wheel-drive performance,” Ward’s AutoWorld, pp. 38–41.
7.
Cutillas, S., Bossis, G., Lemaire, E., Meunier, A. and Cebers, A., 1998, “Experimental and Theoretical Study of the Field Induced Phase Separation in Electro-and Magnetorheological Suspensions,” Proc., 6th Int. Conf. on ER, MR Suspensions and Their Applications, M. Nakano and K. Koyama eds., World Scientific, Singapore, pp. 149–155.
8.
Filisko, F. E. and Henley, S., 2000, “Parameters Affecting Lamellar Formations in ER Fluids: An Alternative Model for ER Activity,” Proc., 7th International Conference on Electrorheological (ER) Fluids and Magneto-Rheological (MR) Suspensions, R. Tao ed., World Scientific, Singapore, pp. 143–151.
9.
Gross, M., Kiskamp, S., Eisele, H., Zhu, Y. and Liu, J., 1998, “On the Interaction of Dipolar Chains,” Proc., 6th International Conference on ER Fluids, MR Suspensions and Their Applications, M. Nakano and K. Koyama eds., World Scientific, Singapore, pp. 519–527.
10.
Volkova, O., Bossis, G., Carletto, P. and Cebers, A., 2000, “Shear Banded Structures and Nematic to Isotropic Transition in MR Fluids,” Proc., 7th International Conference on Electrorheological (ER) Fluids and Magneto-Rheological (MR) Suspensions, R. Tao ed., World Scientific, Singapore, pp. 358–365.
11.
von Pfeil, V., Graham, M.D., Klingenberg, D.J. and Morris, J.F., 2001, “A Two-Fluid Model for Electro- and Magnetorheological Suspensions,” Proc., 8th International Conference on ER Fluids and MR Suspensions, G. Bossis ed., World Scientific, Singapore, pp. 759–765.
12.
Bechtel, S., Washington, G., Ahmadkhanlou, F. and Wang, Y., 2004, “Microstructural Analysis and Control of Magneto-Rheological Fluid,” Proc. IMECE04, Vol. 2.
13.
Klingenberg
D. J.
,
van Swol
F.
and
Zukoski
C. F.
,
1991
, “
The Small Shear Rate Response of Electrorheological Suspensions. II. Expansion Beyond the Point-Dipole Limit
,”
J. of Chemical Physics
,
94
(
9
), pp.
6170
6178
.
14.
Hass
K. C.
,
1993
, “
Computer Simulations of Nonequilibrium Structure Formation in Electrorheological Fluids
,”
Physical Review E
,
47
(
3
), pp.
3362
3373
.
15.
Mohebi
M.
,
Jamasbi
N.
and
Liu
J.
,
1996
, “
Simulation of the Formation of Nonequilibrium Structures in Magnetorheological Fluids Subject to an External Magnetic Field
,”
Physical Review E
,
54
(
5
), pp.
5407
5413
.
16.
Volkova, O., Bossis, G. and Lemeire, E., 1998, “Magnetorheology of Model Suspensions,” Proc., 6th Int. Conference on Electrorheological (ER) Fluids, Magneto-Rheological (MR) Suspensions and Their Applications, M. Nakano and K. Koyama eds., World Scientific, Singapore, pp. 528–534.
17.
Ly
H. V.
,
Reitich
F.
,
Jolly
M. R.
,
Banks
H. T.
and
Ito
K.
,
1999
, “
Simulations of Particle Dynamics in Magnetorheological Fluids
,”
J. of Computational Physics
,
155
, pp.
160
177
.
18.
Sim
H. G.
,
Ahn
K. H.
and
Lee
S. G.
,
2003
, “
Three-dimensional Dynamics Simulation of Electrorheological Fluids under Large Amplitude Oscillatory Shear Flow
,”
J. of Rheology
,
47
(
4
), pp.
879
895
.
19.
Climent
E.
,
Maxey
M. R.
and
Karniadakis
G. E.
,
2004
, “
Dynamic of Self-Assembled Chaining in Magnetorheological Fluids
,”
Langmuir
,
20
(
2
), pp.
507
513
.
20.
Wereley, N.M., 2003, “Nondimensional Analysis of EWlectrorheological and Magnetorheological Dampers Using a Herschel-Bulkley Constitutive Model,” Proc., 4th ASME-JSME Joint Fluids Engineering Conference, FEDSM2003-45046.
21.
Lee
D. Y.
and
Wereley
N. M.
,
1999
, “
Quasi-steady Herschel-Bulkley Analysis of Electro- and Magnetorheological Flow Mode Dampers
,”
J. of Intelligent Material Systems and Structures
,
10
(
10
), pp.
761
769
.
22.
Bird, R.B., Curtiss, F.C., Armstrong, R.C. and Hassager, O., 1987, Dynamics of Polymeric Liquids, Vol. 1 and 2, 2nd Edition, John Wiley and Sons, New York.
23.
Lipscomb II, G.G., 1986, “Analysis of Suspension Rheology in Complex Flows,” Ph.D. dissertation, University of California, Berkeley.
24.
Larson, R.G., 1999, The Structure and Rheology of Complex Fluids, Oxford University Press, New York.
25.
Lipscomb
G. G.
,
Denn
M. M.
,
Hur
D. U.
and
Boger
D. V.
,
1988
, “
The Flow of Fiber Suspensions in Complex Geometries
,”
Journal of Non-Newtonian Fluid Mechanics
,
26
, pp.
297
325
.
This content is only available via PDF.
You do not currently have access to this content.