Flow Induced by Torsional Oscillations of a Disk in a Rotating Visco-Elastic Fluid

The flow due to torsional oscillations of a disk about a steady rotation in an elastico-viscous fluid which is also rotating has been analyzed.The flow is characterized by two circularly polarized waves travelling with different velocities.It is found that the depth of penetration or wave length decreases for 0 0.58 k  and increases for > 0.59 k where k is the elastic parameter and  is the frequency parameter.The unsteady axial velocity at large distance from the disk has a phase lead for <2  and a phase lag for >2  .