COMBINED INFLUENCE OF NONLINEAR THERMAL RADIATION, THERMAL-DIFFUSION AND DIFFUSION-THERMO ON THE DYNAMICS OF STEADY BOUNDARY LAYER FLOW

Abstract

This study investigates the combined in uence of nonlinear thermal radiation, thermal- di usion and di usion-thermo on the dynamics of steady boundary layer ow. The ra- diative heat ux in the energy equation is described using Roseland approximation. The governing non-linear partial di erential equations with the boundary conditions which model the transport phenomena are transformed using suitable similarity variables into a system of coupled non-linear ordinary di erential equations. Thereafter, a qualitative analysis of the problem is investigated by postulating theorems and proofs on existence and uniqueness of solution and stability of the ow model. The resulting dimension- less system of equations governing the model are solved numerically via Runge-Kutta- Fehlberg Method in conjunction with shooting iteration technique. Also, the results for the dimensionless velocity, temperature and concentration distributions are presented in graphs for various values of the thermophysical parameters controlling the ow regime. Finally, numerical values of physical quantities, such as the local Skin-friction coe cient, local Nusselt number, and the local Sherwood number are presented in tabular form. The results showed that uid temperature increases while the species concentration decreases with an increase in Dufour number or a decrease in Soret number.