Viskositeetit
Viskositeetit refers to viscosity values, describing a fluid's resistance to flow and deformation under shear. It depends on composition, temperature, and pressure, and affects how easily a liquid moves. In many fluids, viscosity also changes with shear rate, so measurement conditions must be specified when comparing values.
Two commonly used quantities are dynamic (shear) viscosity μ and kinematic viscosity ν. Dynamic viscosity has units of
Viscosity is measured with viscometers. Capillary viscometers determine flow time through a tube; rotational viscometers measure
Viscosity typically decreases with temperature, following Arrhenius-like behavior for many liquids. Non-Newtonian fluids—such as polymer solutions
Understanding viscosity is crucial in lubrication, coatings, food, cosmetics, pharmaceuticals, and polymer processing, influencing pump design,