Posted on 04/21/2015 8:48:47 AM PDT by stickandrudder
There are a number of "non-Newtonian fluids" that exhibit this behavior. One, polydimethylsiloxane, is (or was) the main ingredient of Silly Putty. It was heavily researched as a possible element of for a "lock-up" transmission during the energy crisis of the 1970s.
I don't think the use of these compounds for body armor is a new idea.
I wonder how it works with aimed bullets.
It’s an Oobleck.
Oobleck is a non-Newtonian fluid; it has properties of both liquids and solids. You can slowly dip your hand into it like a liquid, but if you squeeze the oobleck or punch it, it will feel solid.
Just like Silly Putty, and, that stuff the guys were using in the episode of Big Bang with the speaker.
Shear Thickening Fluid for daily wear! The STF Uniform makes sense. Anyone who didagrees can STFU.
“The institute is being tight-lipped on what exactly their fluid is made of”
I’m thinking it’s probably just the optically pure L-isomer form of the ordinarily racemic Flubber mixture purified via stereochemistry separation techniques. In other words, it’s probably just L-Flubber.
use it but have a layer of Kevlar over it as well-
They’ve got a heated version called SHTF.
Pretty cool concept. I’m reminded of a similar idea from the opening scene in “Final Fantasy” where Marines jump out of a drop ship onto a previously deployed gas layer on the ground which cushions their fall.
In other words, they can quickly change from liquid to rock-hard solid when they're hit with something forceful, like a stray bullet, for example.
The term for shear thickening is "rheopectic" and the behavior is "rheopexy."
One typical example is a bucket of sand that has more than enough water to fill the void space between the packed particles. Once that space is filled, additional water will permit the particles to pass over each other, thus making it possible to stir the sand-water mixture. But if one tries to stir faster, the grains interfere with each other more stongly, thus causing shear-thickening behavior. That shear-thickening is rheopexy.
On the other hand, some liquid/solid particle interactions exhibit thinning (lower viscosity) when shear rate is increased. These pastes quickly regain their high viscosity after stirring ceases. This is called "thixotropy" and is exhibited with some fluids like mayonnaise. Clay-water suspensions also may show thixotropy.
A "Newtonian" fluid has the same viscosity throughout its rate of deformation.
FYI
That is not correct. "Silly Putty" is rheopectic, and might even be the basis for this "fluid armor."
Don’t know about bullets, but I saw a baseball player get drilled in the ribs with a fastball the other day and I wonder if that might be a good application.
Rheopexy would be opposite. At low shear rate, without a containier having rigid walls, the substrate would melt into a pool--like the liquid in the liquid armor.
That's a fact, not a joke.
In jump school there used to be a claim that the Russians experimented with dropping paratroops without parachutes, into snow banks, but I have never been able to verify it or label it a myth.
Once out in the public their first lawsuit will no doubt be over someone swallowing it then getting punched in the gut and being ‘eviscerated’ by the spreading shcokwave. It’ll happen in a McDonalds in an Amish neighborhood no doubt ... recorded by several innocent bystanders.
I am so screwed.
I am so screwed.
What Would Laz Do?
“Hit it again!”
I am so screwed.
Want.
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