DRAG MODIFICATIONS FOR A SPHERE IN A ROTATIONAL MOTION AT SMALL, NONZERO REYNOLDS AND TAYLOR NUMBERS - WAKE INTERFERENCE AND POSSIBLY CORIOLIS EFFECTS

Matched asymptotic expansion methods are used to establish governing equations of Oseen type for a tethered sphere that describes a circular path and a stationary sphere subjected to a rotating fluid in an 'antisedimentation' tube. The two cases are shown to be significantly different, in contrast to an earlier presentation (Davis & Brenner 1986), because only the latter is subject to the Coriolis force. The evaluation of the force and torque coefficients is much improved, enabling better comparisons to be made with the classical rectilinear trajectory result of Proudman & Pearson (1957).