is the study of the deformation and flow of matter
. The term rheology was coined by Eugene Bingham, a professor at Lehigh University
, in 1920, from a suggestion by Markus Reiner, inspired by the Heraclitus
' famous expression "panta rhei": everything flows. Rheology has important applications in the engineering sciences and in physiology
. Hemorheology is the study of the flow properties of blood
Basic rheological terms are:
- Shear rate and elongation rate
- Shear stress
- Newtonian law
Fluids can be categorized as:
- Newtonian fluids (the fluid viscosity is constant) and
- non-Newtonian fluids (the fluid viscosity depends on the stresses acting on the fluid) which can by subclassified into
- generalized non-Newtonian fluids (also called purely viscous fluids) and
- viscoelastic fluids.
Rheological properties are determined by means of rheometry.
Journals covering rheology include: