Shear rate

Shear rate is a term from kinematics. It describes the spatial change of the flow rate in liquids. As there are frictional forces in flowing media, various flow rates at various positions of a liquid also mean that a transmission of energy takes place. The shear rate is used in rheology to define the viscosity. It is the coefficient of proportionality between shear stress and shear velocity. The layered flow in laminary flowing media is observed here. The unit of measurement is s-1. This parameter also plays a big role in the design specification of static mixers as the characteristics of several media may change decisively at high shear rates.