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In this article, we use the Buongiorno model to study the three-dimensional tangent hyperbolic nanofluid flow over a stretched sheet. The study investigates the impact of velocity slip on the flow and heat transfer features in a tangent hyperbolic nanofluid. For a better fit with experimental observations. We assume that the nanoparticle mass flux at the boundary is zero as opposed to a prescribed concentration at the surface. Using appropriate transformations, we reduce the partial differential equations that describe the momentum, energy, and concentration transport to ordinary differential equations. Numerical solutions of the equations are obtained using the spectral method. Graphical illustration of the physical influence of various parameters on the flow features, the skin friction coefficient, and the local Nusselt number is given. The results indicate, that particle Brownian motion has a negligible impact on the rate of heat transfer. The impact of the modified Weissenberg number, a measure of the ratio of elastic to viscous forces, causes a reduction in the fluid velocity. The results are shown to be good agreement with those in related studies in the literature. K E Y W O R D Shyperbolic nanofluid, MHD flow, spectral method, stretching sheet

The present study investigates the effect of Cattaneo‐Christov thermal and solutal diffusion on the stagnation point flow of Walters' B nanofluid past an electromagnetic sheet subject to velocity, thermal, and solutal slips. The study analyzed the role of electromagnetic fields. In addition, the authors introduced the heat transfer aspect due to Brownian motion and thermophoretic force. The numerical solution of the transformed governing equations employed the spectral local linearization method. Comparisons showed an excellent agreement with the numerical data presented in previous notable works. The study reveals that the developed electromagnetic field due to the arrangement of the sheet causes accelerated fluid motion, and diminution of nondimensional temperature and concentration. In addition, augmented velocity, thermal, and solutal slips develop the corresponding descending boundary layers. The augmented short memory coefficient enhances the skin friction coefficient. The Cattaneo‐Christov thermal and solutal diffusion upsurge the heat and mass transfer rates from the electromagnetic sheet, respectively.

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In this paper we study the effects of thermal radiation, heat and mass transfer on the unsteady magnetohydrodynamic(MHD) flow of a three dimensional Casson nanofluid. The flow is subject to partial slip and convective conditions. The traditional model which includes the effects of Brownian motion and thermophoresis is revised so that the nanofluid particle volume fraction on the boundary is not actively controlled. In this respect the problem is more realistic. The dimensionless governing equations were solved using the spectral quasi-linearisation method. This work aims to fill the gap in existing literature by showing the effects of porosity, magnetic field and stretching ratio parameter on the flow of the Casson Nanofluid model over a porous linearly stretching sheet with the incorporation of the nanoparticles on the concentration boundary condition. It is observed that increase in the unsteadiness of the flow tends to decrease the momentum, thermal and nanoparticles volume fraction profiles. The results are benchmarked with previously published results.

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This paper presents a two-dimensional unsteady laminar boundary layer mixed convection flow heat and mass transfer along a vertical plate filled with Casson nanofluid located in a porous quiescent medium that contains both nanoparticles and gyrotactic microorganisms. This permeable vertical plate is assumed to be moving in the same direction as the free stream velocity. The flow is subject to a variable heat flux, a zero nanoparticle flux and a constant density of motile microorganisms on the surface. The free stream velocity is time-dependent resulting in a non-similar solution. The transport equations are solved using the bivariate spectral quasilinearization method. A grid independence test for the validity of the result is given. The significance of the inclusion of motile microorganisms to heat transfer processes is discussed. We show, inter alia, that introducing motile microorganisms into the flow reduces the skin friction coefficient and that the random motion of the nanoparticles improves the rate of transfer of the motile microorganisms.

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