3D flow of variable properties viscoelastic nanofluids with impacts of Arrhenius energy and Cattaneo–Christov double-diffusion

Abstract

In several situations, particularly, flow of viscoelastic nanofluids, the dynamic viscosity and thermal conductivity should be considered as variables due to their roles in various practical applications. Therefore, this article aims applying the Cattaneo–Christov double-diffusion theory to investigate the three-dimensional (3D) forced flow of second-grade viscoelastic nanofluids over a permeable stretching surface. The properties of the mixture are considered to be variables where the dynamic viscosity is exponentially varied with temperature and the thermal conductivity and Brownian motion are linearly dependent on temperature and concentration, respectively. The included medium is isotropic porous, and both heat generation and thermal radiation impacts are assumed. At the surface, the nanoparticles are either active or passively controlled, and the convective boundary conditions are considered for the surface temperature. The solution methodology is based on similarity transformations, and the numerical technique is based on 4th-order Runge-Kutta method. The major outcomes revealed that the growth in thermal relaxation time δ e and viscoelastic parameter K causes gradually decreases in temperature and nanoparticles features. Also, constant dynamic viscosity gives higher velocity features compared to the variable case. Furthermore, the considered range of thermal conductivity coefficient ε 1 gives an enhancement in rate of the heat transfer by 5.26%.