Digital Magazine "Maths and Science Adventure" Digital Magazine "Maths and Science Adv_1st issue | Page 7

DIG IT AL
Shear
MAGA ZINE
thickening
A fluid is shear thick-
ening if the viscosity
of the fluid increases
as the shear rate in-
creases. A common
example
of
shear
thickening fluids also
known as dilatant, is a
mixture of cornstarch
and water. You have
probably seen exam-
ples of this on TV or
the internet, where
„MA T HS
A ND
SC IENC E
ADV ENT UR E”
plastics, are ubiquitous in industrial
and biological processes. Common
examples include ketchup, paints
and blood.
people can run over
this kind of solutions
and yet, they will
sink if they stand
still.
Bingham plastic
Shear thinning
Fluids that have a linear shear
stress/shear strain relationship re-
quire a finite yield stress before
they begin to flow (the plot of shear
stress against shear strain does not
pass through the origin). These flu-
ids are called Bingham plastics.
Fluids are shear
thinning if the vis-
cosity decreases as
the shear rate in-
creases. Shear thin-
ning fluids, also
known as pseudo-
But how does deformation depend on shear stress?
Bingham plastic
Shear thinning
Shear thickening
Applications of non
newtonian fluids:
- bulletproof vests
Modern applications of
PAGE
these fluids are found
in the manufacture in-
dustry. The require-
ment for vests that are
lightweight, flexible and
resistant to penetration
has led the industry to
develop products that
are baseed on such
non-Newtonian fluids.
- oobleck bullet
Another similar use of such flu-
ids is the oobleck bullet that is
same as plastic bullets. The
purpose of such bullets is to
repel furious crowds rather than
causing their
death
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