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

  • Ahmed J. Shkarah Mechanical Engineering Department Collegeof Engineering University of Thi-Qar
Keywords: Heat transfer, forced convection, Non-Newtonian fluid, analytical solution, viscous dissipation, Graetz’s problem, laminar flow


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