Nonsimilar solutions for double-diffusion boundary layers on a sphere in micropolar fluids with constant wall heat and mass fluxes

Abstract

a b s t r a c tThis work presents nonsimilar boundary layer solutions for double-diffusion natural convection near a sphere with constant wall heat and mass fluxes in a micropolar fluid. A coordinate transformation is employed to transform the governing equations into nondimensional nonsimilar boundary layer equations and the obtained boundary layer equations are then solved by the cubic spline collocation method. Results for the local Nusselt number and the local Sherwood number are presented as functions of the vortex viscosity parameter, Schmidt number, buoyancy ratio, and Prandtl number. Higher vortex viscosity tends to retard the flow, and thus decreases the local convection heat and mass transfer coefficients, raising the wall temperature and concentration. Moreover, the local convection heat and mass transfer coefficients near a sphere in Newtonian fluids are higher than those in micropolar fluids.

Roughness‐induced effects on the thermomicropolar fluid flow through a thin domain

“…Step 4. Finally, the estimates of the rescaled unknown are obtained by applying to estimates of the unknowns the change of variables (14). □…”

“…Although there have been a number of recent papers concerning engineering applications of the thermomicropolar fluid model (see, e.g., Refs. [14][15][16][17], the rigorous treatments for such models are very sparse. Most recently, the system (1) has been studied in Ref.…”