Non-Newtonian liquid?

[Skew ChiDAMN!!]

Anybody got any ideas WHAT fluid this is? :eek:

http://www.youtube.com/watch?v=f2XQ97XHjVw

[Shedhand]

They filled a pool with a mix of cornstarch and water made on a concrete mixer truck. It becomes a non-newtonian fluid. When stress is applied to the liquid it exhibits properties of a solid.

Let a fluid be traveling in the http://scienceworld.wolfram.com/physics/nimg190.gif direction with velocity u(y). A Newtonian fluid is one for which the strain rate (http://scienceworld.wolfram.com/physics/StrainRate.html)

<table align="center" width="100%"> <tbody><tr valign="middle"><td align="center" nowrap="nowrap">http://scienceworld.wolfram.com/physics/nimg192.gif</td> <td align="right" width="10"> (1)</td></tr> </tbody></table>

is equal to the vertical velocity gradient

<table align="center" width="100%"> <tbody><tr valign="middle"><td align="center" nowrap="nowrap">http://scienceworld.wolfram.com/physics/nimg193.gif</td> <td align="right" width="10"> (2)</td></tr> </tbody></table>

As shown in strain rate (http://scienceworld.wolfram.com/physics/StrainRate.html), this also implies

<table align="center" width="100%"> <tbody><tr valign="middle"><td align="center" nowrap="nowrap">http://scienceworld.wolfram.com/physics/nimg194.gif</td> <td align="right" width="10"> (3)</td></tr> </tbody></table>

so

<table align="center" width="100%"> <tbody><tr valign="middle"><td align="center" nowrap="nowrap">http://scienceworld.wolfram.com/physics/nimg195.gif</td> <td align="right" width="10"> (4)</td></tr> </tbody></table>

Experimentally, a large number of fluids are found to exhibit this behavior. The shear stress (http://scienceworld.wolfram.com/physics/ShearStress.html), which is linear in the strain rate with a constant of proportionality known as the dynamic viscosity (http://scienceworld.wolfram.com/physics/DynamicViscosity.html), is then

<table align="center" width="100%"> <tbody><tr valign="middle"><td align="center" nowrap="nowrap">http://scienceworld.wolfram.com/physics/nimg196.gif</td> <td align="right" width="10"> (5)</td></tr> </tbody></table>

The viscous force between layers of fluid is therefore

<table align="center" width="100%"> <tbody><tr valign="middle"><td align="center" nowrap="nowrap">http://scienceworld.wolfram.com/physics/nimg197.gif</td> <td align="right" width="10"> (6)</td></tr> </tbody></table>

where http://scienceworld.wolfram.com/physics/nimg29.gif is the dynamic viscosity (http://scienceworld.wolfram.com/physics/DynamicViscosity.html) which is assumed to be independent of u.

[silentC]

Yeah, anyone can cut and paste :p But what does it mean?

[echnidna]

It means its mud made from cornstarch instead of good ole dirt.

[Wood Butcher]

Its chemistry name is Oobleck. Absolutely great experiment to do with kids (outside)

[Eddie Jones]

What kind of dill would fill their pool up with mud?

Am I missing something here?

[Daddles]

Shouldn't Shedhand's post be in Open Slather :confused:

Richard

[echnidna]

Shouldn't Shedhand's post be in Open Slather :confused:

Richard

course not,

if'n the mods don't unnerstand it why ban it? :p

[Wood Butcher]

Had a look around youtube at the similar vids.

This one is awesome http://www.youtube.com/watch?v=WnDKOc0Ag28 (http://www.youtube.com/watch?v=lDzampa3xrc)

[ian]

Yeah, anyone can cut and paste :p But what does it mean?basicly there are five types of fluid
ones like air
ones like water and oil
thixotropic ones that look solid but turn liquid when shaken (quick sand is possibly the most common)
non-newtonian ones that look liquid but behace like a solid when stressed

of course the most important type are the alcoholic ones


ian

[Skew ChiDAMN!!]

Just a mix of cornstarch, eh? I can see my li'l bros is gonna kill me when he see what I'm gonna do to his nice 16" honeycomb mid-ranges...

But it should be interesting until then. ;):D

[Shedhand]

Just a mix of cornstarch, eh? I can see my li'l bros is gonna kill me when he see what I'm gonna do to his nice 16" honeycomb mid-ranges...

But it should be interesting until then. ;):Dhehehehe you evil bugga...:D:D:D
PS: I have absolutely no clue as to what the chicken footprints mean. I think a guy named Jesus might have invented it......;)
:rolleyes:

[Shedhand]

I wonder if Corn Starch is the same as Corn Flour :confused:

[AlexS]

basicly there are five types of fluid
ones like air
ones like water and oil
thixotropic ones that look solid but turn liquid when shaken (quick sand is possibly the most common)
non-newtonian ones that look liquid but behace like a solid when stressed

of course the most important type are the alcoholic ones


ian

When I saw the vid I immediately thought of thixotropi liquids as being the exact opposite of the vid.
When I worked in Bougainville, the entire mine site had been under a layer of fine volcanic tuff (like a fine clay). Around the place this stuff used to be heaped up by earthworks and soaked by the frequent rain. Looked like a heap of dirt until a truck when past, and the heap would collapse and flow like a liquid.

[echnidna]

Now for the $64 question....


is Strawberry Jelly a solid or a liquid ? :p

[Shedhand]

Now for the $64 question....


is Strawberry Jelly a solid or a liquid ? :pdepends on the temp and if you've added the water yet.:p

[Iain]

Now for the $64 question....


is Strawberry Jelly a solid or a liquid ? :p

A viscous liquid, or low viscosity solid, oh sod it, how long is a piece of string.