What exactly is a fluid? It helps to know the characteristics!
- Fluids are a state of matter in which a substance cannot hold a shape.
- Fluids can be a liquid, a gas, or air.
- Newtonian fluids flow easily and continually under an applied stress.
- Liquids are said to flow in a continuum.
- Some fluids, such as air and gas, are said to be compressible.
Some fluids are Newtonian. These fluids have a:
- linear relationship between the shear stress and the shear rate.
- definable coefficient of viscosity.
- constant coefficient of viscosity.
- predictable behavior.
Some fluids are Non-Newtonian. These fluids:
- do not behave like Newtonian fluids.
- are subject to shear stress from other factors such as temperature and pressure.
- a coefficient of viscosity that is not possible to calculate.
- have unpredictable behavior.