## Non-Newtonian fluids, time independent

The viscosity of a Non-Newtonian time independent fluid is dependent not only on temperature but also on shear rate.

Depending on how viscosity changes with shear rate the
flow behaviour is characterised as:

- shear thinning - the viscosity decreases with increased shear rate
- shear thickening - the viscosity increases with increased shear rate
- plastic - exhibits a so-called yield value,
*i.e.*a certain shear stress must be applied before flow occurs

Shear thinning fluids are also called *pseudoplastic* and
shear thickening fluids are also called *dilatant*.

Examples of shear thinning fluids:

- paint
- shampoo
- slurries
- fruit juice concentrates
- ketchup

Examples of shear thickening fluids:

- wet sand
- concentrated starch suspensions

Examples of plastic fluids:

- quark
- tomato paste
- tooth paste
- hand cream
- some ketchups
- grease

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