Thermal radiation effect on unsteady mixed convection boundary layer flow and heat transfer of nanofluid over permeable stretching surface through porous medium in the presence of heat generation

Here, we study the effect of mixed convection and thermal radiation on unsteady boundary layer of heat transfer and nanofluid flow over permeable moving surface through a porous medium. The effect of heat generation is also discussed. The equations governing the system are the continuity equation, momentum equation and the heat transfer equation. These governing equations transformed into a system of nondimensional equations contain many physical parameters that describe the study. The transformed equations are solved numerically using an implicit finite difference technique with Newton's linearization method. The thermo-physical parameters describe the study are the mixed convection parameter α, $0\ll \alpha \ll 10$, the Radiation parameter Rd, $0\ll Rd\ll 1.0$, porous medium parameter k, $0\ll k\ll 1.0$, the nanoparticles volume $\varphi$,$0\ll \ll 0.2$, the suction or injection parameter f_w, $-1\ll f_w\ll 1$, the unsteadiness parameter A_t, $1\ll A_t\ll 2$ and the heat source parameter λ = 0.5 .The influence of the thermo-physical parameters is obtained analytically and displayed graphically. Comparisons of some special cases of the present study are performed with previously published studies and a good agreement is obtained.