Cu-Al2O3/Water Hybrid Nanofluid Stagnation Point Flow Past MHD Stretching/Shrinking Sheet in Presence of Homogeneous-Heterogeneous and Convective Boundary Conditions

Abstract

The intent of this research was to present numerical solutions to homogeneous–heterogeneous reactions of the magnetohydrodynamic (MHD) stagnation point flow of a Cu-Al2O3/water hybrid nanofluid induced by a stretching or shrinking sheet with a convective boundary condition. A proper similarity variable was applied to the system of partial differential equations (PDEs) and converted into a system of ordinary (similarity) differential equations (ODEs). These equations were solved using Matlab’s in-built function (bvp4c) for various values of the governing parameters numerically. The present investigation considered the effects of homogeneous–heterogeneous reactions and magnetic field in the hybrid nanofluid flow. It was observed that dual solutions were visible for the shrinking sheet, and an analysis of stability was done to determine the physically realizable in the practice of these solutions. It was also concluded that hybrid nanofluid acts as a cooler for some increasing parameters. The magnetohydrodynamic parameter delayed the boundary layer separation; meanwhile, the nanoparticle volume fraction quickened the separation of the boundary layer that occurred. In addition, the first solution of hybrid nanofluid was found to be stable; meanwhile, the second solution was not stable. This study is therefore valuable for engineers and scientists to get acquainted with the properties of hybrid nanofluid flow, its behavior and the way to predict it.

Hybrid Nanofluid Flow over a Permeable Non-Isothermal Shrinking Surface

“…Moreover, dual solutions of hybrid nanofluid flow were examined by Waini et al [34][35][36][37][38][39]. Other physical aspects have been considered by several authors [40][41][42][43][44][45][46][47][48][49] and review papers are also available [50][51][52][53][54][55].…”

Numerical investigation of the thermo‐hydraulic performance of water‐based nanofluids in a dimpled channel flow using Al2O3, CuO, and hybrid Al2O3–CuO as nanoparticles

“…Therefore, in this paper, a compound technique of heat transfer enhancement is shown, which involves both the modification of geometry and improvement in the coolant. The paper evaluates the thermal performance of both nanofluids (CuO + water, + water) and hybrid nanofluids (−CuO + water) 48 as well as the impacts of spherical dimpled surfaces in the channel with reduced computational length using computational methods. The variation of entropy generation for different coolants was discussed to give detailed information about the coolant's performance.…”

Double Solutions and Stability Analysis of Micropolar Hybrid Nanofluid with Thermal Radiation Impact on Unsteady Stagnation Point Flow

“…Due to the occurrence of non-uniqueness in the present research, the stability analysis is executed by referring to the work of Merkin [62], Weidman et al [63], and Harris et al [64]. These analyses have been implemented by other researchers too (see for example the work of [14][15][16]25,26,32,39,59]). Some important steps are implemented to identify the stability of solutions, i.e., (i) introducing a new dimensionless time variables and similarity variables, (ii) implement the linear eigenvalue equations, and (iii) relax the boundary conditions.…”

“…This new kind of fluid, however, shows a great advance in heat conductivity and it proved by the work of Madhesh and Kalaiselvam [36], Tahat and Benim [37], Devi and Devi [38], etc. Following this, mathematical investigation specifically in boundary layer flow in hybrid nanofluid has attracted a few researchers to explore it in various surfaces such as in stretching/shrinking sheet [39], curved surface [40], thin needle [41], Riga plate [42], etc. By opting the novel idea of hybrid nanofluid, Subhani and Nadeem [43] scrutinized the behavior of hybrid nanofluid (Cu-TiO 2 /water) in micropolar fluid in a porous medium past an exponentially stretching sheet and point out that the heat transfer rate for micropolar hybrid nanofluid is greater than micropolar nanofluid.…”