It is frequently measured using a device called a capillary viscometer. Kinematic viscosity is a measure of the resistive flow of a fluid under the influence of gravity. The similarity to Newton's second law of motion ( F = m.a) should be apparent. The more usual form of this relationship, called Newton's equation, states that the resulting shear of a fluid is directly proportional to the force applied and inversely proportional to its viscosity. Viscosity is the ratio of the shearing stress (F/A) to the velocity gradient (Δ v x/Δ z or dv x/ dz) in a fluid. This is an Open Access article distributed under the terms of the Creative Commons Attribution License ( ), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. At the low viscosity, long − capillary viscometers are used as primary standards which are directly calibrated water. The national standard of viscosity provided by TUBITAK UME consists of a set of ubbelohde viscometers covering the measuring range of kinematic viscosities from about 0.5 mm 2/s to 100 000 mm 2/s. It is a common practice to use the viscosity of water as the metrological basic of viscometry. An increasing number of national metrology institutes and accredited laboratories provide viscometer calibration with reference liquids in a wide viscosity range.

The aim of this study to evaluate the results of the primary level viscosity measurement system and stabinger viscometer and to compare the measurement results due to the providing traceability of Stabinger viscometer by TUBITAK UME.

Based on our measurement with various liquids, we determine the viscosity values and compare both of the results. * Corresponding author: present study was realized for measuring viscosities of reference liquids using capillary viscometers and Stabinger viscometer SVM 3001 with viscosity interval between 1 mm 2/s and 5000 mm 2/s with temperatures from 20 ☌ to 80 ☌. The Scientific and Technical Research Council of Turkey, National Metrology Institute (TUBITAK UME), Gokce Sevim Sariyerli *, Orhan Sakarya and Umit Yuksel Akcadag

Methods for testing viscosity