Capillary Viscometry: Analysis of Kinetic Energy and Hydrostatic Head Corrections and a More Exact Calculation

Abstract

An extensive experimental investigation and an analysis of previous results on capillary viscometry have resolved many of the contradictory results and conclusions concerning the constancy of the kinetic‐energy correction factor, usually denoted m. This factor is shown to be constant within experimental error at flow rates corresponding to Reynolds numbers from 50 to 1500. The reported gross changes in m, as the Reynolds number is varied, are shown to derive from calculation errors and from neglect of certain established corrections. A more accurate calculation of the kinetic‐energy correction term, to take into account the variation in flow rate within a single determination, is required if the calibration and test materials have greatly different kinematic viscosities.