Effects of Wall Confinement and Power-Law Fluid Viscosity on Nusselt Number of Confined Spheres

Effects of wall confinement on the heat transfer phenomena of confined spherical particles in power-law fluids are numerically investigated. The spherical particle is held at constant temperature and a power-law fluid is flowing past the particle in a confining tube. Heat transfer takes place from the heated sphere to the surrounding fluid. The governing conservation equations of mass, momentum, and energy are solved using computational fluid dynamics-based software. The numerical solver is thoroughly validated by comparing the present average Nusselt numbers with existing literature values. On the basis of numerical results, an empirical correlation for the average Nusselt number of a confined sphere in Newtonian and power-law fluids is proposed which can be used in new applications.