Paper 9: A Rotating Cylinder Viscometer for Measurement at Elevated Temperature and Pressure

This paper records some of the recent experimental methods used to determine the viscosity of water. In drawing attention to the many techniques used (most relying upon calibration of the instrument by a fluid of known viscosity), the conclusion may be drawn that an absolute instrument is required which will produce results over a wide range of temperature and pressure.

It has long been known that the rotating cylinder viscometer is capable of a high degree of accuracy, but technical considerations have, in the past, restrained most workers from pursuing this method at high pressures.

Progress in the development of the rotating cylinder instrument for these conditions is described and specific problems encountered with this method are discussed.

This work is a continuation of the design studies of Kjelland-Fosterud (1)† and Whitelaw (2) who both gave considerable thought to the problems associated with this type of instrument. The first instrument to be tested by the author was based on Whitelaw's design but it was found that certain aspects of this instrument required major alteration. A new instrument was set up and has been found suitable for accurate viscosity determination.