Possibility of identifying the viscoplastic properties of liquids in experiments with an oscillating-cup viscometer

Results of a numerical solution of the problem of oscillations of an oscillating-cup viscometer filled with a viscoplastic liquid are presented. It is shown that near the rotation axis, a stagnant zone arises, whose boundary changes position during the oscillations. The effect of the plastic properties of the liquid on the frequency and damping coefficient of oscillations of the viscometer is determined. A method of identifying the viscoplastic properties using observed oscillation parameters is proposed. __________ Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 47, No. 6, pp. 59–63, November–December, 2006.