Bingham plastic

As Bingham fluids are referred to special, named after Eugene Cook Bingham, non-Newtonian fluids. Its dynamic viscosity is still not a function of shear rate ( or shear rate ), resulting in a linear flow behavior:

With

This means that a Bingham fluid first begins with a minimum shear stress of the yield point to flow. Below it, it behaves like an elastic body. Such materials are described in rheology by the Bingham model.

Examples

Examples of Bingham fluids are ketchup, toothpaste, yeast dough and certain wall colors, but also blood. Also technically suspensions used as electro- and magneto-rheological fluids can be described by a Bingham model. These fluids are only transferred to a floating state when a certain shear stress is reached. This happens, for example, when it presses the wall part on the wall and with color rolls. At this moment, the shear forces become so great that the color turns into a floating state and wets the wall. As long as the color - as far as possible without external application of force - is on the roll, it behaves like an elastic solid, and does not drip off the roll.