Laminar Fully Developed Forced Convection of Power Law Fluid in a Circular Tube

Abstract

Laminar forced convection heat transfer in a non-Newtonian fluid flow inside a pipe has been investigated analytically. Fully developed laminar velocity distributions obtained by a power-law fluid rheology model is used, and viscous dissipation was taken into account. The theoretical analysis of the heat transfer is performed under a constant wall temp. case. An important feature of this approach is that it permits an arbitrary distribution of the surrounding medium temperature and an arbitrary velocity distribution of the fluid. These techniques were verified by a comparison with the existing results. The effects of the Brinkman number and rheological properties on the distribution of the local Nusselt number have been studied. It is shown that the Nusselt number strongly depends on the value of power law index. The Nusselt number sharply decreases in the range of 0 < n < 0.1. However, for n > 0.5, the Nusselt number decreases monotonically with the increasing n, and for n > 1, the values of Nusselt number approach a constant value.