STEADY SLOW ROTATION OF A SPHERE IN A VISCO-ELASTIC LIQUID

Abstract

In this paper, we obtain the fiow due to slow steady rotation of a sphere in a visco-elastic liquid characterized by the constitutive relation given by Rivlin. The non-Newtonian effects are strongly dependent on a non-di- mensional parameter K independent of the angular velocity of the sphere. If 1 < K < 3, we notice four vortices symme~crieally placed around the sphere. When K lies outside this fange, the direction of the flow pattern is the same as that in the Newtollian case but displaced towards the sphere as K decreases. Also the expression for the couple on the sphere has been obtained which depends on K.