Kinematic viscosity is a measure of a fluid's internal resistance to flow under gravitational forces. It is the ratio of absolute viscosity to density. Kinematic viscosity can be obtained by dividing the absolute viscosity of a fluid with the fluid mass density. This value is converted to standard units such as centistokes (cSt) or square millimeters per second, like:
ν = μ / ρ
ν = kinematic viscosity (m2/s)
μ = absolute or dynamic viscosity (N s/m2)
ρ = density (kg/m3)
Measurement of Kinematic Viscosity
Kinematic viscosity is measured by noting the time it takes oil to travel through the orifice of a capillary under the force of gravity (Fig.1). The orifice of the kinematic viscometer tube produces a fixed resistance to flow. Different sized capillaries are available to support fluids of varying viscosity.
Fig. 1 Capillary U-Tube Viscometer
Scopes of Application
The kinematic viscosity tester for petroleum products we use complies with ASTMD445 and ISO3104 standards, which can accurately measure the kinematic viscosity of petroleum products in strict accordance with the standard description.
Alfa Chemistry's Advantages
Chemists from Alfa Chemistry have a great deal of experience in the applications and tests of low molecular weight alcohols, acids and esters. Our experienced chemists are pleased to work with you to solve your problems in scientific research and industrial applications. Please feel free to contact us for more information.