Digital Magazine "Maths and Science Adventure" Digital Magazine "Maths and Science Adv_1st issue | 页面 5

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ferent deformations
(flows) that fluids have.
This question emerges
effortlessly by observ-
ing the flow of honey
and water in the pic-
tures on the right.
Why do fluids pre-
sent viscosity?
Viscosity is presented
due to the collisions
between the fluid mole-
cules, but also because
From the above picture
we observe that:
The fluid layers are lo-
cated between the
of the cohesion forces
of its molecules. For
the study of fluid engi-
neering we use the fol-
lowing simple model.
As you can observe
plane (y = 0) and the
plate to a height of
y = H where the fluid is
impulse.
The velocity of each
layer u x (y) depends on
some kind of fluid is
placed between two
plates. The plate on the
upper side slides at ve-
locity V while the other is
stationary .
its height in relation to
the stationary plate..
When y = 0 u x = 0
When y = H = u x = V
The above observations led Newton to his experimental law of viscosity.
Shear stress
Viscosity
Rate of deformation
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