STEADY FLOW OF A NON-NEWTONIAN FLUID WITH HEAT TRANSFER IN A WAVY CYLINDRICAL TUBE

Abstract

The problem of heat transfer is a steady flow of a Rivlin-Ericksen fluid inside a wavy cylindrical tube is considered. Taking the deformation of the boundary to be small, the equations of momentum and energy have been solved using the perturbation technique_ The solution for the velocity field is then employed to study the nature of the temperature field, the boundary of the tube being maintained at a constant temperature.

It is interesting to note that the velocity field for non-Newtonian and Newtonian fluids is the same while the pressure is modified. The stream lines near the boundary of the tube proceed parallel to it and the deformation of these lines goes on Increasing as the axis is approached where they become straight. However, the deformity of the isotherms goes on increasing towards the axis so much so that between :=7lamda and z= 27'lamda they form closed loops. In this respect also, the Newtonian and the non-Newtonian fluids are fo qnd to bc the same. These features have also been found to exist in the case of low between two wavy walls.