The measurement of the viscosity of liquid systems (pure liquids or their mixtures) and structured fluids such as suspensions, emulsions and polymeric solutions is performed with rotational rheometers. The sample put between two measuring elements is put in motion by applying a torque and the corresponding angular speed is measured (or vice versa). Such macroscopic measurable variables are then converted in local properties, shear stress and shear rates, whose ratio gives the shear viscosity. By changing the torques (or angular speeds) applied the dependence of viscosity on shear stress (or shear rate) can be found (flow curves).

Instruments available:

• Bohlin Instruments C-VOR 120
• Haake MARS III