Mixed Thermal Convection of Power-Law Fluids Past Bodies With Uniform Fluid Injection or Suction

Abstract

Steady laminar flow of power-law fluids past heated two-dimensional or axisym-metric bodies is strongly influenced by the rate of fluid mass transfer at the wall, the buoyancy force, and the characteristics of the power-law fluid. The effects of these parameters on the local skin friction group and heat transfer group are analyzed for wedges of different angles, horizontal cylinders, and spheres. The local heat transfer group, HTG~Nux, for wedge flows is greatly affected by the power-law viscosity index n, and by fluid withdrawal especially when the generalized Prandtl number is relatively high. Fluid suction at larger Prandtl numbers also generates high HTG values for cylinders and spheres. However, the local skin friction group, SFG~Cf, for cylinders or spheres increases with fluid injection and decreases with suction largely because of buoyancy effects.