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Specialty Chemistry Forums => Chemical Engineering Forum => Topic started by: PEPAKURAPROP1 on May 19, 2017, 03:19:46 AM

Title: Non-Newtonian Fluids
Post by: PEPAKURAPROP1 on May 19, 2017, 03:19:46 AM

Hi,

I been looking around, but the internet definitions are too advanced for me... What is plastic flow liquids, and what are some examples? What is the difference between pseudo plastics and thixotropy?           

Title: Re: Non-Newtonian Fluids
Post by: Corribus on May 19, 2017, 12:18:23 PM

One of my favorite examples of a non-Newtonian fluid can be found at the beach: moist sand. It was one of the reasons I became interested in physics. As a teenager, I marveled how if you take moist sand - which normally behaves like a solid - and apply a compression force, it practically liquefies. Apparently some beach-dwelling creatures have evolved to take advantage of this property, as it assists in their burrowing.

I guess the classic example used in fluid dynamics is ketchup, which exhibits thixotropy (sheer thinning when agitated). That's why it's so hard to get it to come out of a (glass) bottle unless you give it a good whack :)