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This research highlights the physical significance of nanoparticle in magnetohydrodynamics (MHD) stagnation point flow (SPF) over a stretchable surface with porosity effect and boundary slip phenomenon. The nanoliquid and its advanced thermal activity are shown extra auspicious results when the flow is considered over a permeable (porous) medium. In addition, the nanoparticles of radius size play an important role in the thermal performance of nanofluid. In this work, copper is accounted as a nanoparticle and water as a base fluid. Nanomanufacturing, surface engineering, coatings, nanofabrication and tribology are some of the important and special mechanical characteristics of nanoparticles [D. Guo, G. Xie and J. Luo, J. Phys. D, Appl. Phys.  47, 013001 (2014)]. The flow is electrically conducted in the presence of applied magnetic field. Mixed convection, Joule heating and viscous dissipation effects are accounted in the mathematical modeling. Appropriate similarity variables are used to convert the couple governing system of PDEs into ordinary ones and results are computed through bvp4c via shooting concept. From the obtained results, it is divulged that the velocity field increases against higher estimations of unsteady parameter, while it declines versus larger magnetic parameter and radius of nanoparticles. The engineering interest like skin friction and Nusselt number is mathematically calculated and results are computed in a tabular form, and their obtained outcomes show that the magnitude of skin friction rises against unsteadiness parameter and radius of nanoparticles. This study is an extended work of [Verma et al.Chem. Eng. J. Adv.12, 100366 (2022)] with some extra flow assumptions like MHD, SPF, Joule heating, heat generation/absorption and viscous dissipation. Obtained results are compared with [Grubka and Bobba J. Heat Transf.  107, 248 (1985)], Verma et al. [Chem. Eng. J. Adv.  12, 100366 (2022)] and [Elbashbeshy and Emam Therm. Sci.15,  477 (2011)] found 100% accuracy with them. The most important result of the conducted study is that the skin friction coefficient immensely augments subject to larger estimations of radius of nanoparticles when permeability of porosity is less. [ABSTRACT FROM AUTHOR]

In present times modern electronic devices often come across thermal difficulties as an outcome of excessive heat production or reduction in surface area for heat exclusion. The current study is aimed to inspect the role of iron (III) oxide in heat transfer enhancement over the rotating disk in an axisymmetric flow. Water is utilized as base fluid conveying nano-particle over the revolving axisymmetric flow mechanism. Additionally, the computational fluid dynamics (CFD) approach is taken into consideration to design and compute the present problem. For our convenience, two-dimensional axisymmetric flow configurations are considered to illustrate the different flow profiles. For radial, axial, and tangential velocity profiles, the magnitude of the velocity, streamlines, and surface graphs are evaluated with the similarity solution in the computational fluid dynamics module. The solution of dimensionless equations and the outcomes of direct simulations in the CFD module show a comparable solution of the velocity profile. It is observed that with an increment in nanoparticle volumetric concentration the radial velocity decline where a tangential motion of flow enhances. Streamlines stretch around the circular surface with the passage of time. The high magnetization force 0 ≤ m 1 ≤ 6 resist the free motion of the nanofluid around the rotating disk. Such research has never been done, to the best of the researchers' knowledge. The outcomes of this numerical analysis could be used for the design, control, and optimization of numerous thermal engineering systems, as described above, due to the intricate physics of nanofluid under the influences of magnetic field and the inclusion of complex geometry. Ferrofluids are metallic nanoparticle colloidal solutions. These kinds of fluids do not exist in nature. Depending on their purpose, ferrofluids are produced using a variety of processes. One of the most essential characteristics of ferrofluids is that they operate in a zero-gravity environment. Ferrofluids have a wide range of uses in engineering and medicine. Ferrofluids have several uses, including heat control loudspeakers and frictionless sealing. In the sphere of medicine, however, ferrofluid is employed in the treatment of cancer via magneto hyperthermia. [ABSTRACT FROM AUTHOR]

The significance of back-propagated intelligent neural networks (BINs) to investigate the transmission of heat in spinning nanofluid over a rotating system is analyzed in this study. The buoyancy effect is incorporated along with the constant thermophysical properties of nanofluids. Levenberg–Marquardt intelligent networks (ANNLMBs) are employed to study heat transmission by using a trained artificial neural network. The system of highly non-linear flow governing partial differential equations (PDEs) is transformed into ordinary differential equations (ODEs) which is taken as a system model. This achieved system model is utilized to generate data set using the "Adams" method for distinct scenarios of heat transmission investigation in a spinning nanofluid over a rotating system for the implementation of the proposed ANNLMB. Additionally, with the help of training, testing, and validation, the approximate solution of heat transmission in a spinning nanofluid in a rotating system is obtained using a BNN-based solver. The generated reference data achieved employing the proposed artificial neural network based on a Levenberg–Marquardt intelligent network is distributed in the following manner: training at 82%, testing at 9%, and validation at 9%. Furthermore, MSE, histograms, and regression analyses are performed to depict and discuss the impact of the varying influence of key parameters, such as unsteadiness "s" in spinning flow, Prandtl number effect "pr", the rotational ratio of nanofluid and cone α 1 and buoyancy effect γ 1 on velocities F ′ G and temperature Θ profiles. The mean square error confirms the accuracy of the achieved results. Prandtl number and unsteadiness decrease the temperature profile and thermal boundary layer of the rotating nanofluid. [ABSTRACT FROM AUTHOR]

This research investigates the two different hybrid nanofluid flows between two parallel plates placed at two different heights, y 0   and y h , respectively. Water-based hybrid nanofluids are obtained by using A l 2 O 3 , T i O 2 and C u as nanoparticles, respectively. The upper-level plate is fixed, while the lower-level plate is stretchable. The fluid rotates along the y-axis. The governing equations of momentum, energy and concentration are transformed into partial differential equations by using similarity transformations. These transformed equations are grasped numerically at MATLAB by using the boundary value problem technique. The influence of different parameters are presented through graphs. The numerical outcomes for rotation, Nusselt, Prandtl, and Schmidt numbers are obtained in the form of tables. The heat transfer rate increases by augmentation in the thermophoresis parameter, while it decays by increasing the Reynolds number. Oxide nanoparticles hybrid nanofluid proved more efficient as compared to mixed nanoparticles hybrid nanofluid. This research suggests using oxide nanoparticles for good heat transfer. [ABSTRACT FROM AUTHOR]

This article is an attempt to explore the heat transfer features of the steady three-dimensional rotating flow of magneto-hydrodynamic hybrid nanofluids under the effect of nonlinear radiation over the bi-directional stretching surface. For this purpose, two different nano-particles, namely silver (Ag) and molybdenum di-sulfide (MoS2), were selected. Three different conventional base fluids were utilized to form desired hybrid nanofluids such as water (H2O), engine oil (EO), and ethylene glycol (EG). We obtained steady three-dimensional highly nonlinear partial differential equations. These highly nonlinear partial differential equations cannot be solved analytically, so these equations were handled in MATLAB with the BVP-4C technique with convergence tolerance at 10−6. The graph depicts the effect of the magnetization effect, thermal radiation, and stretching ratio on rotating hybrid nanofluids. Additionally, the impact of thermal radiation on the heat coefficient of three different hybrid nanofluids is being investigated. The augmentation in magnetization decreases the primary velocity, whereas the increment in radiation enhances the primary velocity. The stretching ratio and the presence of higher magnetic forces increase the temperature profile. The concentration profile was enhanced with an increment in the magnetic field, stretching, and rotation ratio. The maximum Nusselt number was achieved for the Ag-MoS2/EO hybrid nanofluid. It was concluded that augmentation in nonlinear radiation enhances the heat transfer coefficient for the examined cases (I) and (II) of the hybrid nanofluids. The Nusselt number doubled for both the examined cases under nonlinear radiation. Moreover, it was discovered that Ag-MoS2/water produced the best heat transfer results under nonlinear radiation. Therefore, the study recommends more frequent exploration of hybrid nanofluids (Ag-MoS2/water) when employing nonlinear radiation to analyze the heat transfer coefficient. [ABSTRACT FROM AUTHOR]

Thermal heat generation and enhancement have been examined extensively over the past two decades, and nanofluid technology has been explored to address this issue. In the present study, we discuss the thermal heat coefficient under the influence of a rotating magneto-hydrodynamic hybrid nanofluid over an axially spinning cone for a prescribed wall temperature (PWT) case. The governing equations of the formulated problem are derived by utilizing the Rivlin–Ericksen tensor and boundary layer approximation (BLA). We introduce our suppositions to transform the highly non-linear partial differential equations into ordinary differential equations. The numerical outcomes of the problem are drafted in MATLAB with the of help the boundary value problem algorithm. The influences of several study parameters are obtained to demonstrate and analyze the magneto-hydrodynamic flow characteristics. The heat and mass transfer coefficients increase and high Nusselt and Sherwood numbers are obtained with reduced skin coefficients for the analyzed composite nanoparticles. The analyzed hybrid nanofluid (SWCNT-Ag–kerosene oil) produces reduced drag and lift coefficients and high thermal heat rates when compared with a recent study for SWCNT-MWCNT–kerosene oil hybrid nanofluid. Maximum Nusselt (Nu) and Sherwood (Sh) numbers are observed under a high rotational flow ratio and pressure gradient. Based on the results of this study, we recommend more frequent use of the examined hybrid nanofluid. [ABSTRACT FROM AUTHOR]

Numerous heat transfer applications, such as heat exchangers, solar trough collectors, and fields including food processing, material research, and aerospace engineering, utilize hybrid nanofluids. Compared to conventional fluids, hybrid nanofluids exhibit significantly enhanced thermal conductivity. The aim of this work is to explore flow and heat transmission features under of magneto-hydrodynamic bioconvective flow of carbon nanotubes over the stretched surface with Dufour and Soret effects. Additionally, comparative dynamics of the carbon nanotubes (SWCMT − MWCNT/C2H6O2 with SWCMT − MWCNT/C2H6O2 − H2O) flow using the Prandtl fluid model in the presence of thermal radiation and motile microorganisms has been investigated. Novel feature Additionally, the focus is also to examine the presence of microorganisms in mixture base hybrid nanofluid. To examine heat transfer features of Prandtl hybrid nanofluid over the stretched surface convective heating is taken into consideration while modeling the boundary conditions. Suitable similarity transform has been employed to convert dimensional flow governing equations into dimensionless equations and solution of the problem has been obtained using effective, accurate and time saving bvp-4c technique in MATLAB. Velocity, temperature, concentration and microorganisms profiles have been demonstrated graphically under varying impact of various dimensionless parameters such as inclined magnetization, mixed convection, Dufour effect, Soret effect, thermal radiation effect, and bioconvection lewis number. It has been observed that raising values of magnetization (0.5 ≤ M ≤ 4), mixed convection (0.01 ≤ λ ≤ 0.05) and inclination angle (0° ≤ α ≤ 180°) enhance fluid motion rapidly in Ethylene glycol based Prandtl hybrid nanofluid (SWCMT − MWCNT/C2H6O2) when compared with mixture base working fluid of carbon nanotubes SWCMT − MWCNT/C2H6O2 − H2O). Raising thermal radiation (0.1 ≤ Rd ≤ 1.7) and Dufour number (0.1 ≤ Du ≤ 0.19) values improves temperature profile. Moreover, a good agreement has been found between the current outcome and existing literature for skin friction outcomes. [ABSTRACT FROM AUTHOR]

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]

This research analyzes the three-dimensional magneto hydrodynamic nanofluid flow through chemical reaction and thermal radiation above the dual stretching surface in the presence of an inclined magnetic field. Different rotational nanofluid and hybrid nanofluids with constant angular velocity ω ∗ for this comparative study are considered. The constitutive relations are used to gain the equations of motion, energy, and concentration. This flow governing extremely non-linear equations cannot be handled by an analytical solution. So, these equations are transformed into ordinary differential equalities by using the similarity transformation and then handled in MATLAB by applying the boundary values problem practice. The outcomes for the considered problem are accessed through tables and graphs for different parameters. A maximum heat transfer amount is observed in the absence of thermal radiation and when the inclined magnetic field and axis of rotation are parallel. [ABSTRACT FROM AUTHOR]

In this exploration, temperature-dependent Yamada–Ota and Xue hybrid nanoliquid models are investigated over a curved stretchable surface embedded in an absorbent media. Hybrid nanofluids are formed by the combination of single and multi-walled carbon nanotubes (CNTs) as nanoparticles with engine oil as base fluid. The goal of this study is to interpret how the modified Fourier law combined with temperature-dependent thermal conductivity, Newtonian heating and variable heat source/sink enhances thermal performance. A mathematical formulation of the problem is illustrated in the curvilinear coordinates. Highly nonlinear dimensionless ODEs are solved numerically by engaging the bvp4c approach. The impression of the key parameters is illustrated graphically. Drag force coefficient and Nusselt number are highlighted through tables. It is comprehended that the fluid velocity decays on augmenting the velocity slip parameter while elevates on amplifying the curvature parameter. Furthermore, an enhancement in the temperature field is noted for the conjugate parameter. A significant correlation with the existing outcomes is perceived when a comparison with the existing literature is made. [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]

The present study possesses the mathematical computational analysis for mixed convection nanofluid (CuO–water) flow in a lid‐driven parallelogram enclosure with corrugated walls. A partially heated source is located at the bottom corrugated wall. The remaining portions of upper and lower corrugated boundaries are adiabatic. The verticals walls are kept cold. The flow dynamic established with wall undulation and inclined Lorentz forces generate complex mathematical formulation via partial differential equations. Finite element method is implemented to get numerical interpretation of these equations. The simulation is performed against various emerging parameters and the outcomes in terms of isotherms, streamlines and line graphs. The results are recorded against various Richardson numbers (10−2≤Ri≤102)$(10^{-2}\le Ri \le 10^{2})$, Hartman number (0≤Ha≤100)$(0\le Ha \le 100)$, nanoparticles volume fraction (0≤ϕ≤0.2)$(0 \le \phi \le 0.2)$, and amplitude of the corrugated horizontal walls (0.02≤Am≤0.10)$(0.02\le A_m \le 0.10)$. It is observed that against smaller Richardson number streamlines indicate forced convection flow while at higher Richardson number flow divert toward free convection regime. Additionally, heat transportation is maximum when magnetic field is applied in perpendicular direction as well as at maximum amplitude of wall undulations. [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]

Solar thermal systems have low efficiency due to the working fluid's weak thermophysical characteristics. Thermo-physical characteristics of base fluid depend on particle concentration, diameter, and shapes. To assess a nanofluid's thermal performance in a solar collector, it is important to first understand the thermophysical changes that occur when nanoparticles are introduced to the base fluid. The aim of this study is, therefore, to analyze the hydrodynamic and heat characteristics of two different water-based hybrid nanofluids (used as a solar energy absorber) with varied particle shapes in a porous medium. As the heat transfer surface is exposed to the surrounding environment, the convective boundary condition is employed. Additionally, the flow of nanoliquid between two plates (in parallel) is observed influenced by velocity slip, non-uniform heat source-sink, linear thermal radiation. To make two targeted hybrid nanofluids, graphene is added as a cylindrical particle to water to make a nanofluid, and then silver is added as a platelet particle to the graphene/water nanofluid. For the second hybrid nanofluid, CuO spherical shape particles are introduced to the graphene/water nanofluid. The entropy of the system is also assessed. The Tiwari-Das nanofluid model is used. The translated mathematical formulations are then solved numerically. The physical and graphical behavior of significant parameters is studied. [ABSTRACT FROM AUTHOR]

There are various implementations of common fluids in industrial and chemical processes. With the cooperation of the nanoparticles, the lower thermal properties of such fluids can be augmented. By using a new kind of nanofluid namely hybrid nanofluid, the heat transfer rate of such fluids can be boosted more quickly. The main intention of this research is on entropy analysis in the stagnant point flow of a hybrid nanofluid. The mixed convection nonlinear thermal radiative flow on a stretchable vertical sheet is examined under the influences of the induced magnetic field and chemical reactions. The impacts of Joule heating, partial slips and viscous dissipation are also involved. After the execution of the appropriate similarity transformations, the constituting equations of the flow problem emerge as the nonlinear dimensionless setup of ordinary differential equations. An amplification is examined in the velocity field, entropy generation, and induced magnetic field relative to the mixed convection parameter. With the improved Brinkman number, an augmentation is developed in the entropy of the system. Moreover, both the heat transfer rate and the surface drag force exhibit an accelerating behavior relative to the mixed convection parameter. [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]

In a porous medium, we have examined sinusoidal two-dimensional transport enclosed porous peristaltic boundaries having an Eyring Powell fluid with a water containing Al 2 O 3 . The determining momentum and temperature equations are solved semi-analytically by using regular perturbation method and Mathematica. In present research only free pumping case and small amplitude ratio is studied. Mathematical and pictorial consequences are investigated for distinct physical parameters of interest like porosity, viscosity, volume fraction and permeability to check the effects of flow velocity and temperature. [ABSTRACT FROM AUTHOR]

Carbon nanotubes (CNTs) are nanoscale tubes made of carbon atoms with unique mechanical, electrical, and thermal properties. They have a variety of promising applications in electronics, energy storage, and composite materials and are found as single-wall carbon nanotubes (SWCNTs) and double-wall carbon nanotubes (DWCNTs). Considering such alluring attributes of nanotubes, the motive of the presented flow model is to compare the thermal performance of magnetohydrodynamic (MHD) mono (SWCNTs)/Ethylene glycol) and hybrid (DWCNTs- SWCNTs/Ethylene glycol) nanofluids over a bidirectional stretching surface. The thermal efficiency of the proposed model is gauged while considering the effects of Cattaneo-Christov heat flux with prescribed heat flux (PHF) and prescribed surface temperature (PST). The flow is assisted by the anisotropic slip at the boundary of the surface. The system of partial differential equations (PDEs) is converted into a nonlinear ordinary differential system by the use of similarity transformations and handled using the bvp4c numerical technique. To depict the relationship between the profiles and the parameters, graphs, and tables are illustrated. The significant outcome revealed that the fluid temperature rises in the scenario of both PST and PHF cases. In addition, the heat transfer efficiency of the hybrid nanoliquid is far ahead of the nanofluid flow. The truthfulness of the envisioned model in the limiting scenario is also given. [ABSTRACT FROM AUTHOR]

The present study analyzes the partially ionized three-dimensional Casson nanoliquid flow over a porous stretched bi-directional surface with C–C heat flux. The heat transfer analysis is conducted in the presence of homogeneous–heterogeneous with surface catalyze reaction. The existence of a surface catalyzed reaction triggers the chemical reaction and executes it in the minimum possible time. The impact of the Ohmic dissipation and partial slip boundary condition is also assumed. The mathematical ODE's is solved numerically. The velocity profile decreases for the higher Casson and porosity parameter while rises for the greater Hall current. The performance of the Drag force coefficient varied values of different parameters is characterized in Tabular form. It is disclosed that the liquid velocity has dwindled for the growing ion-slip parameter. The endorsement of the stated model is done by comparing it with a previously published article. An outstanding harmonization is attained in this case. [ABSTRACT FROM AUTHOR]

The main purpose of this study is to scrutinize the axisymmetric flow of second-grade nanofluid with variable viscosity near a stagnation point under the influence of the Cattaneo–Christov double diffusion model. A Riga plate is assumed to be the source of the three-dimensional flow. The consequences of the anisotropic slip conditions and the Buongiorno model are included in the formulation of the constituting equations of the fluid flow. The highly nonlinear ordinary differential equations are developed with the executions of the relevant similarity transformations on the problem's governing equations. For the asymptotic analysis, the appropriate expansions are implemented on the nonlinear system of ordinary differential equations. The bvp4c technique of the MATLAB package is implemented on the nonlinear ordinary equations for the numerical solutions. In order to explore the impact of the parameter slip factor on the pattern of velocities, temperature, and concentration profiles, several graphs are plotted. From this study, we conclude that the normalized velocities boost up with the amplification in the slip factor parameter but the temperature profile exhibits a declining behavior. The concentration field exhibits the accelerating behavior relative to the slip parameter. [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]

The current paper focused on an unsteady bio-convective Maxwell nanofluid flow subject to convective boundary conditions through an exponentially stretching curved surface. The transportation of heat and mass are observed with thermophoresis and Brownian effect along with chemical reaction. The mathematical flow model is converted into a system of nonlinear system of ODEs via suitable transformation. The numerical solution of a nonlinear system of equations is established with the help of bvp4c MATLAB technique. It is deeply studied that in the curved surface, the pressure is never ignored. The graphical representation of several parameters along the temperature, concentration, microorganism density and velocity distribution is presented. It is examined that the greater estimation of curvature parameter boosts the temperature of fluid and concentration of nanoparticles, although a reverse trend is seen for the velocity profile. Further, it is examined from the numerical values that the heat and mass transfer rate reduce consequently with the enlargement of the curvature parameter. [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]

The nanofluid flows play a vital role in many engineering processes owing to their notable industrial usage and excessive heat transfer abilities. Lately, an advanced form of nanofluids namely "hybrid nanofluids" has swapped the usual nanofluid flows to further augment the heat transfer capabilities. The objective of this envisaged model is to compare the performance of two renowned hybrid nanofluid models namely Hamilton–Crosser and Yamada–Ota. The hybrid nanoliquid (TiO2-SiC/DO) flow model is comprised of Titanium oxide (TiO2) and Silicon carbide (SiC) nanoparticles submerged into Diathermic oil (DO). The subject flow is considered over a stretched surface and is influenced by the magnetic dipole. The uniqueness of the fluid model is augmented by considering the modified Fourier law instead of the traditional Fourier law and slip conditions at the boundary. By applying the suitable similarity transformations, the system of ordinary differential equations obtained from the leading partial differential equations is handled by the MATLAB solver bvp4c package to determine the numerical solution. It is divulged that the Yamada–Ota model performs considerably better than the Hamilton–Crosser flow model as far as heat transfer capabilities are concerned. Further, the velocity reduces on increasing hydrodynamic interaction and slip parameters. It is also noted that both temperature profiles increase for higher hydrodynamic interaction and viscous dissipation parameters. The envisioned model is authenticated when compared with an already published result in a limiting case. [ABSTRACT FROM AUTHOR]

This comparative research investigates the influence of a flexible magnetic flux and a chemical change on the freely fluid motion of a (MHD) magneto hydrodynamic boundary layer incompressible nanofluid across an exponentially expanding sheet. Water and ethanol are used for this analysis. The temperature transmission improvement of fluids is described using the Buongiorno model, which includes Brownian movement and thermophoretic distribution. The nonlinear partial differential equalities governing the boundary layer were changed to a set of standard nonlinear differential equalities utilizing certain appropriate similarity transformations. The bvp4c algorithm is then used to tackle the transformed equations numerically. Fluid motion is slowed by the magnetic field, but it is sped up by thermal and mass buoyancy forces and thermophoretic distribution increases non-dimensional fluid temperature resulting in higher temperature and thicker boundary layers. Temperature and concentration, on the other hand, have the same trend in terms of the concentration exponent, Brownian motion constraint, and chemical reaction constraint. Furthermore, The occurrence of a magnetic field, which is aided by thermal and mass buoyancies, assists in the enhancement of heat transmission and wall shear stress, whereas a smaller concentration boundary layer is produced by a first-order chemical reaction and a lower Schmidt number. [ABSTRACT FROM AUTHOR]

The present study ventilates shear-dependent viscosity to examine the non-Newtonian rheology of Ostwald-de-Waele nanofluid flow over a rotating disk of variable thickness in a Darcy-Forchheimer permeable medium. Heat transfer phenomenon is witnessed by adding non-uniform heat source-sink with melting heat transfer. The effectiveness of surface catalysis in the process of homogeneous and heterogeneous reactions is also analyzed. The Buongiorno nanofluid model is used for the fluid flow assumptions. The sketched model contains the system of partial differential equations. The procedure of using similarity transformation is adopted to obtain the ordinary differential equations. Simulations are performed to obtain the numerical results via the bvp4c numerical scheme. The numerical values of drag force coefficient and heat transfer rate are the properties of physical interest. Large values of Prandtl number are favorable to boost the heat transfer phenomenon. The thermal profile is increased for both pseudoplastic and dilatant fluid models. The power-law index is more influential than the disk thickness index. Surface catalysis triggers the reaction more efficiently. [ABSTRACT FROM AUTHOR]

This comparative study inspects the heat transfer characteristics of magnetohydrodynamic (MHD) nanofluid flow. The model employed is a two-phase fluid flow model. Water is utilized as the base fluid, and zinc and titanium oxide ( Zn and TiO 2 ) are used as two different types of nanoparticles. The rotation of nanofluid is considered along the z-axis, with velocity   ω * . A similarity transformation is used to transform the leading structure of partial differential equations to ordinary differential equations. By using a powerful mathematical BVP-4C technique, numerical results are obtained. This study aims to describe the possessions of different constraints on temperature and velocity for rotating nanofluid with a magnetic effect. The outcomes for the rotating nanofluid flow and heat transference properties for both types of nanoparticles are highlighted with the help of graphs and tables. The impact of physical concentrations such as heat transference rates and coefficients of skin friction are examined. It is noted that rotation increases the heat flux and decreases skin friction. In this comparative study, Zn -water nanofluid was demonstrated to be a worthy heat transporter as compared to TiO 2 -water nanofluid. [ABSTRACT FROM AUTHOR]

This particular research was conducted with the aim of describing the impact of a rotating nanoliquid on an elasting surface. This specific study was carried out using a two-phase nanoliquid model. In this study engine oil is used as the base fluid, and two forms of nanoparticles are used, namely, titanium oxide and zinc oxide (TiO2 and ZnO). Using appropriate similarity transformations, the arising system of partial differential equations and the related boundary conditions are presented and then converted into a system of ordinary differential equations. These equations are numerically tackled using powerful techniques. Graphs for nanoparticle rotation parameter and volume fraction for both types of nanoparticles present the results for the velocity and heat transfer features. Quantities of physical significance are measured and evaluated, such as local heat flux intensity and local skin friction coefficients at the linear stretching surface. Numerical values for skin friction and local heat flux amplitude are determined in the presence of slip factor. [ABSTRACT FROM AUTHOR]