Rheometer

Rheology is the study of flow and deformation of materials. A rheometer is a laboratory precision instrument used to measure the way in which a viscous fluid (such as emulsions, suspensions, polymer solutions, polymer melts, coatings, inks, food materials, etc.) flows in response to applied forces. It is used for those fluids which cannot be defined by a single value of viscosity and therefore require more parameters to be set and measured than is the case for a viscometer. It measures the rheology of the fluid. There are two distinctively different types of rheometers. Rheometers that control the applied shear stress or shear strain are called rotational or shear rheometers, whereas rheometers that apply extensional stress or extensional strain are extensional rheometers.