Magnetorheological (MR) fluids consist of stable suspensions of magnetic particles in a carrying fluid. Magnetorheological effect is one of the direct influences on the mechanical properties of a fluid. It represents a reversible increase, due to an external magnetic field of effective viscosity. MR fluids and devices have the potential to revolutionize the design of hydraulic systems, actuators, valves, active shock and vibration dampers, and other components used in mechanical systems. At present, there is a compelling need to develop new and improved MR fluids, to lower their production cost through improved manufacturing processes, and to develop MR fluid-based application devices that will demonstrate the engineering feasibility of the MR fluids concept and will highlight the implementation challenges.

1. PRESENTATION ON
MR FLUID
SUBMITTED BY-
DIVYANSH GARG
MECHANICAL DEPARTMENT

2. CONTENT
Smart Fluid……………………………………………………………………………1.
MR Fluid………………………………………………………………………………..2.
Functions of MR Fluid……………………………………………………………3.
How it works…………………………………………………………………………4.
Modes of operation....................................................................5.
1.Flow Mode………………………………………………………………………6.
2.Shear Mode……………………………………………………………………..7.
3.Squeeze-Flow Mode…………………………………………………………8.
Limitation……………………………………………………………………………....9.
Application…………………………………………………………………......10-11.
Advantages of MR Fluid………………………………………………………..12.
Conclusion…………………………………………………………………………….13.
Reference………………………………………………………………………………14.

3. SMART FLUID
• A Smart Fluid is a special type of
fluid whose properties can be
changed by applying an electric
field or magnetic field.
1.

4. What are MR Fluid??
• A magnetorheological fluid (MR fluid) is a
type of smart fluid in a carrier fluid, usually a
type of oil.
• When subjected to a magnetic field,
the fluid greatly increases its apparent
viscosity, to the point of becoming
a viscoelastic solid.
• MR Fluid are non-Newtonian fluid.
• MR fluids are different from ferro-fluid.
2.

5. Functions of MR Fluid
• These are the liquids that change
their properties when we apply a
magnetic field to them.
• When the magnet is in place the
MR fluid turns into a solid.
• When the magnet is removed the
solid instantly reverse into liquid.
3.

6. How it works??
• Fig.a showing the
random distribution of
magnetic particles in
MR fluid.
Fig.a
• Fig.b showing the
behavior of magnetic
particles in a magnetic
field.
Fig.b
4.

8. Modes of operation
• Three modes of operation are there for MR Fluid:-
(i) Flow Mode.
(ii)Shear Mode.
(iii)Squeez Flow Mode.
• In all the above mention case Magnetic field is perpendicular
to the plane of plates, so as to restrict fluid in the direction
parallel to the plate.
5.

9. 1.FLOW MODE
• Both plates are
stationary.
• Fluid is flowing du to
the pressure gradient.
• Magnetic field is
perpendicular to the
direction of flow.
• Application:-Dampers
and shock absorber.
6.

10. 2.SHEAR MODE
• In this mode one plate is
stationary and the other
plate is moving.
• In this mode also magnetic
field is perpendicular to
direction of flow of fluid.
• Shear mode is generally
used to control rotational
motion.
• Applications:-Clutches and
brakes.
7.

11. 3.SQUEEZE-FLOW MODE
• In this mode one plate is
moving relative to the
other ,perpendicular to its
plane.
• This mode is used in
controlling small,
millimeter-order
movement but involving
large forces.
8.

12. LIMITATIONS
• High density.
• High quality fluids are expensive.
• Fluids are subjected to thickening after
prolonged use and need replacing.
• Setting of Ferro particles can be a problem
for some applications.
9.

13. APPLICATION:-
DAMPERS AND SHOCK
ABSORBER
The MR damper has a Built in MR
valve across which the fluid is
forced. The piston of the MR
dampers act as an electromagnet
with the required number of coils
to produce the appropriate
magnetic field.
10.

14. • They are used in
automotive power train
to transmit torque from
the engine to the
transmission and the
vehicle.
• Other applications are
military and defenses,
optics, aero scope and
human prosthesis.
11.

15. Advantages of MR Fluid
• Easy to control- As magnetic field can be
precisely controlled by current driven
electromagnets.
• Have higher magnitude of yield stress-
compared to ER fluids the simple
construction of devices, lower power
requirements for control, fast response.
12.

16. CONCLUSION
• MR Fluid has a wide range of application
and there is a lot of future scope for these
technology.
• But, still there are some limitations of MR
fluid which we have to keep in mind before
using them or find a way to resolve these
limitations.
13.

17. REFERENCES
• www.google.com
• www.wikipedia.com
14.