Bodewadt flow and heat transfer over a stretching stationary disk

The three-dimensional motion of flow due to the rotation of a viscous fluid at a sufficiently large distance from a stationary disk, the so-called classical Bodewadt boundary layer flow, is extended in this paper for the first time in the literature to the case where the stationary disk is permitted to uniformly stretch in the radial direction. The effects of such a stretching mechanism on the flow and heat characteristics are of present concern for this physical problem. A conventional transformation is shown to lead to a set of similarity equations which are coupled and highly nonlinear. It is found that the traditional Bodewadt boundary layer is greatly altered under the influence of radial stretching of the wall. As a consequence of reduction in the momentum boundary layer, the thickness of the thermal boundary layer is also observed to considerably decrease even for moderate strength of stretching. This outcome is prominently important from the technological point of view since the radial stretching may serve to cool down the system in practical applications. (C) 2014 Elsevier Ltd. All rights reserved.