Particle behavior in shear and electric fields: IV. The viscosity of suspensions of nonrotating ellipsoids

Jeffery's calculation of the energy dissipation in a suspension of noninteracting spheroids undergoing slow shear flow is extended for prolate spheroids in Couette flow, when they are prevented from rotating by an external torque, the spheroid axes being perpendicular to the fluid vorticity. The intrinsic-viscosity coefficient (2.5 for freely rotating spheres) is 4 for fixed spheres and 2 for long rods parallel to the fluid streamlines, and becomes indefinitely large for long rods perpendicular to the streamlines. It always exceeds the minimum value for free rotation. A suspension such as this provides a realizable model of a fluid having an unsymmetric stress tensor.