Flow between caoxial rotating disks: with and without externally applied magnetic field

The problem of flow of a Rivlin-Ericksen type of viscoelastic fluid is discussed when such a fluid is confined between two infinite rotating coaxial disks. The governing system of a pair of non-linear ordinary differential equation is solved by treating Reynolds number to small. The three cases discussed are: (I) one disks is held at rest while other rotates with a constant angular velocity, (ii) one disk rorates faster than the other but in the same sense and (iii) the disks rotate in opposite senses and with different angular velocities. The radial, tranverse and axial components of the velocity field are plotted for the above three cases for different values of the Reynolds number. The results obtained for a viscoelastic fluid are compared with those for a Newtonian fluid. The velocity field for case (i) is also computed when a magnetic field is applied in a direction perpendicular to the discs and the results are compared with the case when magnetic field is absent. Some interesting features are observed for a viscoelastic fluid.