On the effect of spatial fractional heat conduction in MHD boundary layer flow using Gr-Fe3O4–H2O hybrid nanofluid

Abstract

In this article, the magnetohydrodynamic boundary layer flow and spatial fractional heat transport of Gr-Fe3O4–H2O hybrid nanofluid on a moving flat plate is investigated. The diffusion terms in the energy equation are modified by incorporating the spatial fractional derivatives using Fourier's law. Moreover, the effect of the joule heating, heat sink/source and viscous dissipation on the energy equation is also taken into account. The optimal collocation method as a new semi-analytical approach is introduced and the effects of physical parameters on the flow and heat transport specifications are obtained and analyzed. It is seen that changing the order of fractional derivatives from 0.92 (fractional diffusion) to 1 (classical diffusion) leads to a growth of the temperature. Furthermore, for the case λ = 0.7, the Nusselt number of Gr-Fe3O4–H2O augments by 22% when compared to Fe3O4–H2O and by 66% when compared to H2O. The results of Nusselt number and Skin friction coefficient for Prandtl number of 0.71 are validated by comparing with both the experimental and numerical studies in the existing literature, which confirms that the optimal collocation method can be successfully used to predict the spatial-fractional MHD boundary layer flow.