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Hybrid nanofluids (HNFs) have potentials applications in automotive industry, heating and cooling systems, biomedical and other fields due to their ability to introduce higher thermal conductivity than standard nanofluids. The purpose of this study is to investigate and compare the thermal transport performance (in the presence of buoyancy force) of two sets of HNFs. The hybrid nanoparticles which is the combination of titanium carbide and aluminium oxide, and the combination of titanium carbide‐copper oxide are taken into account. Both types of hybrid nanoparticles are dispersed in C2H6O2$C_{2}H_{6}O_{2}$ as a subjective fluid over a vertical nonlinear stretching sheet embedded in a porous medium. This will be the first study on the MXene base material TiC$TiC$ , making it possible for MXene‐based materials to enter the fluid dynamics field. Further, MXene material as heat transporting material is studied less and much more is needed for explore its various aspect. The specific combination of Al2O3−TiC$Al_{2}O_{3}-TiC$, and CuO−TiC$CuO-TiC$ is considered because of their promising thermophysical and thermal transport properties. Moreover, considered combination of nanoparticles and the base fluid form a mixture which has thermal relaxation characteristics due to which its deviates from classical Fourier law of heat conduction. Therefore, instead of conventional Fourier's law of heat conduction, the non‐Fourier law of heat conduction is used to formulate the energy equation. It is first time that fhe finite element of method (FEM) is used for such a coupled and nonlinear complex problems of computational fluid dynamics (CFD). The numerical and graphical impacts of magnetic fields, Grashof number, permeable parameter, and thermal relaxation time parameter on velocity, and heat transport are investigated by applying FEM on formulated boundary value problems. In each studied system, increasing the Hartmann number causes an increase the skin friction coefficient and a decrease in the Nusselt number. Moreover, by increasing the thermal relaxation parameter, the temperature of the fluid decreases significantly. The velocity of the modified nanofluids is directly proportional to the Grashof number. The thermal boundary layer thickness (TBLT) and momentum boundary layer thickness (MBLT) of Carreau‐Yasuda (CY)‐HNF (Set II) is greater than CY hybrid nanofluid (CY‐HNF) (Set I) and CY‐Nanofluid (NF), respectively. We believe that the current research work provides new insights to improve the heat transport of nanofluid using appropriate combination of hybrid nanoparticles for practical application. [ABSTRACT FROM AUTHOR]

Sutterby fluid is a viscoelastic fluid and heat and mass transfer in such fluids obeys thermal and concentration memory effects which cannot be analyzed through classical laws of heat conduction and mass diffusion. This is the main motivation toward this study. Therefore, this article considers viscoelastic effects in the presence of thermal and solutal memory effects. A novel theory of heat and mass is simultaneously implemented and generalized models are developed because classical energy and heat equations do not provide accurate information for fluids with memory effect. These generalized models are reducible to their classical cases. Hence, this study considers both generalized and classical aspects. Further, generalized models are solved numerically with the help of the FEM. Results are computed for quantities of engineering interest. The predictions perceived from the analysis are of the use of engineers and industry to design nanofluids with desired thermal properties. A destructive chemical reaction in mono-nanofluid has the highest decreasing effect (relative to tri- and hybrid nanofluids) on the concentration field. A moderate effect of destructive chemical reaction on concentration field in hybrid nanofluid is seen. Mono, hybrid, and tri-nanofluids perceived different magnetic effects. Hybrid nanofluid experiences the greatest magnetic force in comparison with mono and tri-nanofluids. It is seen from the simulations that tri-nanofluid generates the highest heat as a result of Ohmic dissipation. Thus, in comparison with mono and hybrid nanofluid tri-nanofluid offers the highest resistance to the flow of electric current. Moreover, tri-nanoparticles are responsible for an optimized increase in thermal conductivity of Sutterby fluid relative to mono and hybrid nanoparticles. Thus, tri-nanofluid may serve as better coolant, a medium for transporting heat. Destructive chemical reaction in mono-nanofluid has the highest decreasing effect on the concentration field. A moderate effect of destructive chemical reaction on concentration field in hybrid nanofluid is seen. Tri-nanofluid exerts the highest shear stress on the solid boundary while the least shear stress on the wall is seen in the case of mono-nanofluid. A 56% increase in the Nusselt number is noticed if hybrid nanoparticles disperse rather than mono nanoparticles. Similarly, a 59% increase in the Nusselt number is observed if tri-nanoparticles are dispersed rather than mono nanoparticles. Thus the significant rise in heat transfer is possible due to the dispersion of tri-nanoparticles. [ABSTRACT FROM AUTHOR]

This article is a study of heat and mass transport in Maxwell fluid mixed with tri, hybrid and mono nanoparticles. Using conservation laws and correlations among thermophysical characteristics of the base fluid, tri, hybrid and mono nanoparticles, the flow situation is converted into mathematical problems. Boundary layer (BL) approximations are used to approximate these mathematical models. The finite element approach is used to solve the non-dimensional problems numerically. The behavior of viscoelastic materials on momentum, temperature and concentration is investigated. Al 2 O 3 , TiO 2 and SiO 2 are simultaneous dispersed and case of tri (Al 2 O 3 , TiO 2 and SiO 2), hybrid (Al 2 O 3 and TiO 2) and mono (Al 2 O 3) are considered. It is possibly achieved the convergent and mesh-free solutions. Present results are validated. Momentum relaxation time determines the characteristics of fluid to restore momentum changes. Therefore, fluids with more viscoelastic property (with high Deborah number) have smaller viscous region relative to the fluid with smaller Deborah. There is a remarkable decrease in momentum transport versus an increase in Deborah number is noted. It is noted that Deborah number for tri-nanofluid has the smaller effects on flow relative to its impact on the flow of hybrid and mono nanofluids [ABSTRACT FROM AUTHOR]

Two-phase chemical reactions (homogeneous-heterogeneous) in tangent hyperbolic fluid with nanoparticles subjected to heat transfer are modeled using mathematical laws and models. The solutions of governing models are derived by the finite element method (FEM). The solutions are checked to be grid-independent and convergent solutions are obtained which are further used for simulations of effects of various parameters. Shear-thinning and shear-thickening behaviors are predicted from the FEM solutions for the various values of the power-law index and other parameters. The tangent hyperbolic rheological behavior is determined through variation of Wessienberg number. The diverse behavior of fluid motion for the values of the Wessienberg number is observed. Electric current experiences resistance by the particles of the fluid. Hence, more heat is dissipated by the Ohmic mechanism. It is also noted that hybrid nanofluid dissipates more heat than that by mono nanofluid. The Lorentz force induced by the motion of pure and nanofluid is less than that induced by the motion of fluid with hybrid nanoparticles. Thermal relaxation characteristics reinforces the fluid in maintaining its thermal equilibrium and therefore temperature field for both types of fluids has to show a decreasing behavior for an increase in thermal relaxation parameter. The increasing behavior of homogeneous chemical reaction strength on concentration profile is noted whilest the oppositein concentration profile trend is observed for heterogeneous chemical reaction strength. [ABSTRACT FROM AUTHOR]

This article aims to analyze the combined effects of Hall and ion slip currents, Darcy-Forchheimer porous medium, and non-uniform magnetic field under the suspension of hybrid nanoparticles. The flow situation is transformed into mathematical problems using conservation laws and correlations among thermophysical properties of base fluid nano and hybrid nanoparticles. These mathematical models are approximated under boundary layer (BL) approximations. The similarity analysis is performed and the finite element method (FEM) is deployed for the simulations and further investigations regarding non-Fourier behavior of heat and mass transfer. The present results have good agreement with the published benchmark which is a special case of present work. The numerical simulations for the motion of fluid particles under the variation of Weissenberg number are observed and it is noticed that fluid motion decelerates for higher values of Weissenberg number. Significant retardation to the motion of the fluid is seen because of an increase in the Darcy porous medium parameter as an increase in it implies a decrease in the permeability of the porous. Thermal relaxation is the property of the fluid due to which it avoids thermal changes to maintain thermal equilibrium. Therefore, a remarkable decrease in the temperature of fluid exhibiting thermal relaxation characteristics is noticed. It is also noted from numerical experiments that Hall and ion slip currents are responsible to slow down the Ohmic dissipation phenomenon. Thus the property of ionized fluid helps in controlling the thickness of thermal BL. Numerical experiments have shown that the solutal relaxation time for hybrid nanofluid is greater than that for mono nanofluid. Mass diffusivity of the fluid with hybrid nanofluid is less than that of mono nanofluid. [ABSTRACT FROM AUTHOR]

This article compares the impact of different nanoparticles on heat transfer in a Newtonian fluid passing through Darcy Forcheimer's porous space over a convectively heated surface. The correlations for thermo-physical characteristics of nanoparticles (MoS 2 , S iO 2 , Cu , Al 2 O 3) and the base fluid with basic conservation equations are solved numerically. The meshed-free analysis is performed and results are validated. Numerical experiments have shown that an optimized improvement in thermal enhancement is called by S iO 2 and MoS 2 − S iO 2 with respect to Cu and Al 2 O 3. [ABSTRACT FROM AUTHOR]

Rheological model characterized by the shear rate dependent viscosity together with the governing laws for dust particles in fluid with the transfer of heat with the help of nano-structures are utilized for thermal analysis. Solutions of the non-dimensionalized set of constitutive models and necessary conservation laws are found by the finite element method (FEM). The simulations are recorded and important outcomes are extracted from visualization. The fluid has experienced significant retardation to its flow and wall friction on the solid boundary has depicted an increasing behavior as a function of the magnetic field. The flow slows down when viscosity varies for the shear-thinning case. The movement of dust particles in shear rate-dependent viscosity fluid increases as a function of the fluid velocity interaction parameter. Temperature profiles have been noted to increase as a function of specific heat ratio parameter. It is also observed that the temperature of dust particles in mono nanofluid is greater than the temperature of dust particles in a hybrid nanofluid. An increase in the intensity of magnetic fluid results in significant retardation to the fluid containing dust particles. However, this retardation to the flow of hybrid nanofluid is higher than the retardation experienced by the flow of mono nanofluid. Velocity of dust particles increases versus interaction parameter. Moreover, the velocity of hybrid nanofluid is affected more by the interaction parameter than the velocity of nanofluid. Thermal radiations result in a temperature rise. However, radiations emitted by the hybrid nanofluid are stronger than the radiations emitted by a nanofluid. Dust particles in nanofluid are hotter than in hybrid nanofluid. Shear stress on the solid surface increases as a function of the fluid velocity interaction parameter. Further shear stress applied by nanofluid is higher than that by the hybrid nanofluid. [ABSTRACT FROM AUTHOR]