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The homogeneous and heterogeneous reactions can provide important insights into the design and optimization of nanofluid-based heat transfer systems for various applications, such as in thermal management, energy conversion, and cooling. Understanding such pivotal role of homogeneous and heterogeneous reactions in the nanofluid flow modeling, this study aims to explore the consequences on the nanofluid flow comprising graphene oxide/water mixture through a permeable channel impacted by incorporating uniform homogeneous–heterogeneous reactions and heat generation/absorption respectively. The novelty of the presented model is translated by incorporating the thermal conductivity model that integrates the volume fraction of particle, diameter, and nanolayer impacts. The nanofluids possess multi-directional applications including nano drug delivery, cooling of computer microchips, optical devices, etc. The fluid system is formulated using Tiwari and Das nanofluid flow model. The ordinary differential equations (ODEs) are acquired by adopting apposite transformations and numerically computed utilizing the bvp4c method. Moreover, the impacts of the resulting physical parameters on the distributions of temperature, velocity, and nanoparticle volume fraction are examined using graphical representations. It is comprehended that nanofluid velocity declined for the porosity and magnetic parameters. Nevertheless, an upsurge in the fluid temperature is witnessed for the heat generation/absorption parameter. In addition, the heat transfer rate is more prominent in the case of a strong magnetic field. The validity of the envisioned model is also a highlight of this investigation. [ABSTRACT FROM AUTHOR]

The size of nanoparticles influences the viscosity and thermal conductivity of a nanofluid flow. In this exploration, the impacts of the dynamic viscosity and thermal conductivity of the Corcione model on the magneto-hydrodynamics (MHD) Cu-water nanofluid flow over an exponentially stretched surface are examined. It is pertinent to mention that the whole scenario is done at 300 K and the freezing temperatures of 273.15 K with a particle size of 25 nm. The Navier slip and convective boundary conditions are assumed at the surface. A homogeneous single-phase model is adopted to formulate the problem. Nonlinear, coupled momentum, and energy balance nondimensionalized ordinary differential equations (ODEs) are constructed with suitable transformations. To solve these ODEs numerically, a renowned bvp4c technique of MATLAB software is employed. The effects of the arising parameters are represented graphically and numerically and are depicted in tables and graphs. It is witnessed that the velocity of the copper-water nanofluid declined with larger estimations of the volume fraction of nanoparticles, although the temperature distribution showed the reverse tendency. Moreover, at the surface for higher values of the slip parameter, the velocity profile reduces and the temperature of the fluid augments for higher values of the Biot number. The validation of the model is also executed by comparing it with the published result in the limiting case. An outstanding correlation is attained. [ABSTRACT FROM AUTHOR]

The current study focuses on nonlinear convective nanofluid (MoS2 − vacuum pump oil) flow with different shapes in an annular region across coaxial cylinders in a permeable media. At the interface of coaxial cylinders velocity slip and temperature jump conditions are incorporated. The phenomenon of thermal transport is enhanced by amalgamating generalized Fourier law with variable thermal conductivity. The Hamilton-Crosser nanofluid flow model is adopted here. The nonlinear equations that govern the flow are simplified via a similarity transformation. For the numerical solution, the bvp4c algorithm is utilized. Graphical analysis is employed to illustrate how important factors affect the temperature and velocity fields. Computational values of the drag force coefficient and Nusselt number are summarized in tabular form. The study reveals that the velocity field upsurges on enhancing the nonlinear convective and radii ratio parameters. On amplifying the rarefaction and thermal conductivity parameters, the thermal field upsurges. Skin friction coefficient exhibits a decreasing behavior on incrementing the porosity parameter. Heat flux diminishes more rapidly by boosting the concentration of nanoparticles. A considerable correlation is apparent graphically and in tabular form by comparing the results of the current investigation with published studies. [ABSTRACT FROM AUTHOR]

This research aims to examine the combined effects of Cattaneo–Christov heat flux and heat generation/absorption on magnetohydrodynamic (MHD) nanoliquid (Fe3O4-Ethylene glycol) across a linearly stretchable bidirectional surface immersed in a permeable media. The characteristics of nanoliquid (viscosity and thermal conductivity) are a function of temperature and nanoparticle volume fraction. The problem is formulated by considering Corcione's correlation which describes the effective viscosity and thermal conductivity of nanoliquid. The application of Corcione's correlation on a bidirectional surface with a combination of MHD nanofluid comprising the unique combination of (Fe3O4-Ethylene glycol) makes this idea novel and is being presented for the first time. The implementation of appropriate similarity transformation leads to the transition of coupled momentum and energy equations into dimensionless ordinary differential equations (ODEs). These ODEs are numerically addressed by applying a well-known bvp4c method in MATLAB. The outcome of the arising parameters on the velocity and thermal field of nanoliquid are demonstrated graphically and numerically (drag force coefficient and Nusselt number) depicted through tables. It is observed that the porosity and velocity slip parameters combined with the volume fraction of nanoparticles decay velocity field. It is also comprehended that heat transmission augments by escalating the volume fraction of nanoparticles. A strong correlation is reflected in comparing the findings of the current analysis with the preceding literature. [ABSTRACT FROM AUTHOR]

Hybrid nanofluids (HNFs) are a new breed of nanofluids that possess numerous tempting applications encompassing microfluidics, transportation, defense, medical, etc. The objective of this novel exploration is to inspect the behavior of Hamilton–Crosser (H-C) and Yamada–Ota (Y-O) HNF flow models past a stretching cylinder. The H-C model is also used to gauge which particle shape (blade, platelet, cylinder, brick) is more effective in the improvement of the heat transfer rate. The envisioned flow is influenced by the Hall current, Cattaneo–Christov (C-C) heat flux and variable thermal conductivity (TC). The uniqueness of the projected model is the notion of a heterogeneous reaction sprouting on the surface of the cylinder in the presence of an absorbent medium. Owing to this supposition, the chemical reaction occurs in the least possible time. The proposed model's novelty lies in the consideration of the surface catalyzed reaction in the HNF flow models past a stretching cylinder amalgamated with the unique impacts of the Hall current, C-C heat flux and variable TC. The thermal performance of the two renowned models H-C and Y-O is also evaluated. The MATLAB software bvp4c technique is used for numerical outcomes of this coupled system. The analysis depicts that the performance of the Y-O HNF flow model is far above the H-C HNF flow model. It is also inferred from the results that blade-shaped nanoparticles possess higher TC than the other nanoparticles. The heat transfer rate for blade-shaped nanoparticles is stronger than the other nanoparticles. The fluid concentration reduces for higher surface-catalyzed reaction parameter. The corroboration of the proposed model is also given in this study. The comparative results disclosed that in the case of the magnetic parameter M , the minimum error percentage is 0.015% for M = 0. 5 , and permeability parameter λ , the least error percentage is 0.037% for λ = 1. 0. [ABSTRACT FROM AUTHOR]

This paper studies a chemical reactive Maxwell nanofluid flow in porous media with generalized Fourier and Fick laws in the presence of temperature-dependent thermal conductivity and robin conditions past a spinning cone. The characteristics of the fluid flow are examined using the Buongiorno nanofluid model. The equations that regulate the flow are highly nonlinear and are simplified using similarity transformations. Numerical solution is obtained by employing the bvp4c technique. The characteristics of various parameters on tangential and azimuthal velocities, heat, and mass transfers are depicted graphically. An opposing behavior on the tangential and azimuthal velocity fields is depicted in elevating the Deborah number. The solutal field upsurges on increasing the order of the reaction. The mass flux strengthens by augmenting the Schmidt number and solutal relaxation time. The validation of the proposed model in the limiting case is also given. [ABSTRACT FROM AUTHOR]

Hybrid nanofluids (HNF) are the advanced form of nanofluids used for improved heat transfer purposes. Taking this point in mind, the objective of the presented endeavor is to examine the Yamada–Ota HNF flow model comprising (gold–silver/engine oil) over a stretched cylindrical surface and a sheet (as a limiting case) in a permeable medium. The novelty of this research is the consideration of the surface-catalyzed reaction along with the homogeneous–heterogeneous reactions to accelerate the chemical reactions in the shortest possible time. The heat transport phenomenon is strengthened with the support of Joule heating, heat absorption/generation, and the convective heat boundary condition at the surface of the cylinder. The obtained ordinary differential equations are reduced from the partial differential equations using boundary layer theory and are numerically computed using the Keller box method. It is witnessed that for varied estimates of the magnetic parameter, the thermal profile enhances while the velocity field reduces. It is also noted that the fluid concentration is reduced when the surface-catalyzed parameter is enhanced. The validation of the envisioned model in a limiting case is also added to this investigation. [ABSTRACT FROM AUTHOR]

This work leaves to explore the stability of a 2‐D, time free, thermal boundary layer of graphene oxide ethylene glycol (GO‐EG,) where GO‐blood is taken as base nanofluids over a stretchable surface by executing a magnetic field (MHD), coupled stress effects, heat source/sink, and sun‐oriented radiations. This work is done due to the reason that nanofluids have a higher heat conductivity level rather than regular liquids. Nonlinear partial differential equations (N‐PDEs) are modeled utilizing the notable boundary layer equations. Dimensionless ordinary differential conditions (ODEs) are made from the created NPDEs by utilizing dimensional analysis and group theoretic approach. We examine the obtained ODEs through the notable homotopy analysis technique (HAM). The impacts of different parameters on temperature distribution and velocity profiles are shown graphically. However, some tables are constructed in support of the presented study to confirm the stability and convergence of the solutions. The main intentions in this work are to underline the enhancement of traditional heat transfer's thermal conductivity. [ABSTRACT FROM AUTHOR]

• Inclined magnetization and Bioconvection effects are investigated. • Prandtl mixture based hybrid nanofluid model has been utilized to investigate heat transfer over stretched surface. • Motile Micro-organisms migration has been examined with convective condition. • Enhanced Nusselt number and reduced shear stress coefficients are explored. Keeping in view the applications of the hybrid nanofluids in the engineering and industries such as heating and cooling, food processing and heat generation, the focus of this investigation is to explore the effect of mixture base hybrid nanofluid with bio convection effect over linearly convectively heated stretched surface due to the motile micro organisms. The high thermal conductivity of the hybrid nanofluid play significant role in heat transmission. The effect of inclined magnetization on heat transfer of the hybridized bioconvective flow is also examined in this study. Prandtl hybrid nanofluid is used along with silver and magnetite nano-particles. The flow governing equations have been converted into dimensionless form through a suitable similarity transfer. The flow governing model equations are highly non linear and can't be tackled analytically. Therefore, the formulated problem has been addressed using the BVP-4C technique. It was observed that when inclination angle of the magnetization is kept at 60 degrees and magnetic force is in the range of 0.5 < M ≤ 4 , the velocity profile increase. Raising the level of bioconvection impact decline microorganism migration, on contrary high levels of Peclet number reverse this effect. Significant improvement has been observed in heat transfer shift and shear stress by raising thermal Biot number. The outcomes of the present study have been validated with already published results, the outcomes of our results were found in good agreement with previously published results. [ABSTRACT FROM AUTHOR]

The goal of this study is to examine the thermal performance and the flow of hybrid nanofluid over three types of longitudinal wetted fins encompassing thin tip fin, thick tip fin, and fin with a rectangular shape. It is pertinent to mention that both thin and thick tip fins are of exponential profile. The longitudinal fins are of variable thickness with stagnant, stretching, and shrinking cases in a fully wetted circumstance to study the heat augmentation of a conveyer belt. The previous studies considered constant temperature but, in this analysis, the variable type (temperature-dependent) i.e. , exponential and linear forms of thermal conductivities are cogitated for all three cases. A comparison of thermal performance is also elaborated for variables thermal conductivities considering the above-cited three cases. The analysis would be more useful in the designing of fin structures that are helpful to enhance thermal efficiency. This is a pioneering study in this direction. The mathematical model is elucidated numerically. The impact of arising pertinent parameters is arbitrated. It is examined that inverted and rectangular fins possess more heat transfer rate in comparison to the tapered fin. Furthermore, the surface temperature of the stretching fin is higher than the shrinking fin. [ABSTRACT FROM AUTHOR]

Lately, a new class of nanofluids, namely hybrid nanofluids, has been introduced that performs much better compared with the nanofluids when a healthier heat transfer rate is the objective of the study. Heading in the same direction, the present investigation accentuates the unsteady hybrid nanofluid flow involving CuO, Al2O3/C2H6O2 achieved by an oscillating disk immersed in the porous media. In a study of the homogeneous and heterogeneous reactions, the surface catalyzed reaction was also considered to minimize the reaction time. The shape factors of the nanoparticles were also taken into account, as these play a vital role in assessing the thermal conductivity and heat transfer rate of the system. The assumed model is presented mathematically in the form of partial differential equations. The system is transformed by invoking special similarity transformations. The Keller Box scheme was used to obtain numerical and graphical results. It is inferred that the blade-shaped nanoparticles have the best thermal conductivity that boosts the heat transfer efficiency. The oscillation and surface-catalyzed chemical reactions have opposite impacts on the concentration profile. This analysis also includes a comparison of the proposed model with a published result in a limiting case to check the authenticity of the presented model. [ABSTRACT FROM AUTHOR]

The current communication is designed by keeping in the mind high heat transfer capabilities of nanoliquids with the dispersion of diversified-natured nanoparticles in poorly conducting base liquids. Here, an amalgamation of metallic (Cu) and hybridization of metallic and non-metallic oxide (Cu-TiO2) nanoparticles to uplift thermophysical attributes of water is deliberated. The magnetically affected flow between rotating disks under the impact and permeability aspect is assumed. Empirical relations for effective dynamic viscosity, density, and heat capacitance to show mesmerizing features of obliged nanoparticles are also expressed. In addition, mathematical relations also depend on morphological factors like shape, size, and diameter of inducted nanoparticles. The mathematical formulation of the problem is conceded in the form of a system of ODEs after using similarity transformation on dimensional PDEs. Simulations of the complex coupled differential structure are solved by using a numerical approach by employing shooting and Runge–Kutta procedures jointly. The impact of flow concerning variables on associated distributions is revealed through tabular and graphical manner. Quantities of engineering interest associated with work like wall friction and thermal flux coefficients at walls of the disk are also calculated. It is deduced from an examination that the addition of metallic particles raises heat transfer more than non-metallic particles. A significant impression of magnetic field on shear stress is executed by hybrid nanoparticles along the surface of disks. In addition, elevation in Nusselt number and depreciation in skin friction coefficient is revealed against increasing magnitude of nanoparticle volume fraction. A positive trend in skin friction coefficient is manifested against the increasing magnitude of Reynold number. It is also observed that by increasing the size and shape of hybrid nanoparticles thermal conductivity and viscosity of the base fluid increases. [ABSTRACT FROM AUTHOR]

This study examines the transport phenomenon in which host fluid completely mixed with three different nanoparticles types (ternary hybrid nanofluid) has attract scientist's attention for considering of its significance. The primary reason for the rising interest in tri-hybrid nanofluid is its unique ability to improve thermal performance, which is really useful in various heat exchangers. In the present analysis, the main objective of this article is to examining the laminar, time-dependent, incompressible and two dimensional (2D) trihybrid magnetized squeezing flow of a Boger-micropolar nanofluid between non-porous and porous disk to observe the thermal performance of fluid. This model describes the way to attain a more appropriate heat conductor as compared to bi-hybrid, mono nanofluid. The ternary nanofluid is formulated by adding three types of nano size particles with distinct chemical and physical bonds into water as a base liquid. This mixture helps in purification of environment, decomposing destructive substance and other devices that required cooling. At z = − H (1 − a t) 1 / 2 the lower disk is fixed and the liquid is squeezing due to movement of top disk with axial direction. At the lower surface a homogeneous suction/injection is imposed. Energy and velocity slip impacts are also considered at the fixed bottom disk. Appropriate similarity functions are imposed to transform the governs equations into non-linear ordinary differential equations (ODE's) and then numerically solved by bvp4c technique in MATLAB environment. The outcomes are then displayed in graphically to investigate the microrotation, velocity and temperature profiles. The temperature profile decreased against tri-hybrid case in the lower disk case and then are enhanced near to the top disk in tri-hybrid case, so finally, we conclude that ternary nano size particles have an excellent thermal conductivity as compared to single and hybrid nanoparticles. The present results are found to be good agreement with existence literature for limited cases. • Significance of tri-hybrid nanoparticles in thermal management is modeled. • Tiwari and Das model for nanoparticles is taken into account for modeling. • Ternary hybrid nanofluid have an excellent thermal conductivity. • Higher inputs of magnetic field cause to twisting behavior between disk. [ABSTRACT FROM AUTHOR]