The observation and measurement of the non-Newtonian properties of high-temperature fluids using the torsional-oscillation method

The method of torsional oscillation is studied for the possibility of using it for the identification of the rheological type of high-temperature media which are difficult to investigate by other methods. The effects are analyzed which arise when a viscometer is filled with fluids whose rheological properties are described by the Bingham, Ostwald–Weyl, and Balkley–Herschel models. Methods are suggested for the estimation of the viscoplastic and nonlinearly viscous properties, which are based on special features of viscometer motion.