Questions tagged [non-newtonian-fluids]
29 questions
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4 answers
Non-Newtonian Fluid Stop a Bullet?
I just saw a YouTube video about Non-Newtonian fluids where people could actually walk on the surface of the fluid but if they stood still, they'd sink. Cool stuff.
Now, I'm wondering: Could a pool of Non-Newtonian fluid stop a bullet? Why or why…
John
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5
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2 answers
Why are non-Newtonian fluids called non-Newtonian when they follow Newton’s third law?
To my understanding, Newton’s third law states that for every action there is an equal and opposite reaction. Therefor if I punch the non-Newtonian fluid harder, there will be a harder reaction force stopping my hand. So why is the fluid called…
4
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1 answer
If fluids have zero shear modulus, how do I make sense of graphs like strain rate vs shear stress (to classify fluids as Newtonian or non-Newtonian)?
Following the definition on the wiki: Fluids are substances that have zero shear modulus, or, in simpler terms, a fluid is a substance which cannot resist any shear force applied to it.
If fluids have zero shear modulus, shouldn't the shear stress…
2
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2 answers
Limitations of spring and dashpot models in terms of strain meaningfulness
It is common to explain viscoelastic materials with spring and dashpot 1D constructions, e.g:
which represents a Maxwell rheology, usually explained by saying that $ \sigma = \eta \dot{\epsilon}_1 = k \epsilon_2$, and $\epsilon =…
Joce
- 3,365
2
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1 answer
Water coming out of a capillary tube when height is reduced below initial level
Consider a capillary tube of height $H_1$. Water raises to a height $h_1$ in this tube. Now the capillary tube is cut such that its new height is $H_2 < h_1$.
I've read in many textbooks and other online sources that water will rise to a height…
Centelle
- 23
2
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1 answer
Why can shade-balls behave as quick sand?
So I came across this interesting video in which shade-balls were dropped into a swimming pool and people tried to swim around.
Towards the end of the video, a smaller part of the pool is filled with a thick layer of shade-balls and the poster of…
AoZora
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2
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How do I calculate Reynold's number for a non-newtonian fluid?
I am familiar with the known formula to find Reynold's number in a circular pipe for newtonian fluids:
$$\text{Re} = \frac{\rho \bar{v}D}{\mu}$$
where $\rho$ is the density, $\bar{v}$ is the average velocity, and $\mu$ is the viscosity of the…
Pritt Balagopal
- 3,237
2
votes
1 answer
Is quicksand a pseudoplastic or a dilatant fluid?
In the book "Munson and others -Fundamentals of Fluid Mechanics" (at least in my version translated to portuguese) it says that quicksand is a shear thickening fluid but in wikipedia and other sources it says that it is a shear thinning fluid. The…
JoãoVictor
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2
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0 answers
Statistical mechanics arguments for the Newtonian stress-strain model in continuum mechanics
In traditional continuum mechanics, it can be shown using frame-invariance and the Cayley-Hamilton theorem that an isotropic, inelastic* fluid embedded in Galilean space-time must possess the following form of stress-strain rate relationship (if the…
aghostinthefigures
- 3,287
1
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Reference request: an introduction to objective rates and constitutive equations
As a hobby, I am trying to better understand the theory around objective rates, frame invariance and objective constitutive equations in non-Newtonian fluid mechanics. Unfortunately, I have been unable to find a reference at the level I'm interested…
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0 answers
Can you use formula for viscosity derived from Stokes' law to calculate viscosity of non-Newtonian fluid if constant force is applied?
I would like to drop a ball into a test tube containing mixed corn starch and water ( in different ratios) and use Stokes law to get the viscosity for the fixed weight of the ball that I used. Would this be a correct method? Thanks.
Pls Help
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1
vote
1 answer
Falling through a thixotropic ocean -- what would happen?
Drop a heavy incompressible object into water and it would splash and then presumably reach a certain terminal velocity where acceleration is nill.
If you dropped a heavy incompressible object into a sufficiently deep thixotropic, or shear thinning…
Robert Law
- 13
1
vote
1 answer
Is there such a thing as a catastrophic shear thinning liquid?
Non-Newtonian liquids can change their viscosity as a function of shear stress. Shear thinning liquids are those liquids whose viscosity decreases with shear stress. The examples I have seen of such liquids include ketchup and whipped cream.
Is…
Rocketmagnet
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Why did why fluids long molecular chains more likely to have non-Newtonian properties?
I came across a sentence 'fluids with long molecular chains can react in a non-Newtonian manner' in Wikipedia of non-Newtonian fluids, and I did not understand where is the correlation between long molecular with non-Newtonian property.
*By the way,…
Dinoman
- 155
1
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0 answers
Can an electrorheological non-Newtonian fluid be in a definite shape for a short time?
I have seen this Experiment: ELECTRORHEOLOGICAL FLUIDS and balloon Experiment (Stops flow with Static Electricity),
and have seen that simple cornstarch is affected by electrostatic forces.
The mixture of cornstarch and oil is a non-Newtonian…
kryomaxim
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