A Routine High-Pressure Viscometer for Accurate Measurements to 1 GPa

Of the fields for which the piezoviscous property of liquids is of interest, elastohydrodynamics is unique in deriving its existence from this property. Even recent publications in the field, however, have based the description of the pressure variation of viscosity on myths rather than empirical data. The author offers a description of the construction and operation of an easy-to-use viscometer capable of accurate measurements to a pressure of 1 GPa. The classic measurements of Nobel laureate P. W. Bridgman are repeated and examples of measurements on lubricants are given.