Magnetohydrodynamic Hybrid Research Articles

Simulation study of interaction between energetic particles and magnetohydrodynamic modes in the JT-60SA inductive scenario with a flat q≈1 profile

Interactions between energetic particles (EPs), an internal kink mode, and other magnetohydrodynamic (MHD) instabilities in the inductive scenario of JT-60SA (scenario # 2) are simulated with MEGA, a global EP–MHD hybrid code. For this scenario, it was predicted by TOPICS, an integrated transport code that the internal kink mode can be unstable and the sawtooth relaxation results in a flat safety factor (q) profile with q ≈ 1 for r/a⩽0.6 . In this equilibrium, it is found in the simulation results that the stability of the internal kink mode depends strongly on the bulk plasma pressure gradient ( ∇Pb ). In the n = 1 simulations where the toroidal mode number is restricted to n = 0 and 1, the pressure-driven internal kink mode is dominant. In the presence of co-passing EPs generated by the negative-ion-based neutral beam (NB), these EPs transfer energy to the internal kink mode; however, the EP driving rate ( γh ) is much lower than the driving rate from the bulk plasma pressure gradient ( γP ). The mode’s frequency is less than 1 kHz because the toroidal orbit frequency (ω φ ) and poloidal orbit frequency (ω θ ) of the co-passing EPs are approximately equal within the q = 1 surfaces. This mode affects the EP and bulk plasma pressure redistributions. The feasibility of stabilizing the internal kink mode using trapped EPs is also investigated. It is found that the trapped EPs with energy 85 keV generated by the positive-ion-based NBs cannot stabilize the internal kink mode. Stabilization is observed when the injection energy is greater than 500 keV. In the multi-n simulations, where n⩽8 modes are retained, the most unstable modes are high n interchange modes with poloidal number m = n whose linear growth rates exceed that of the pressure-driven internal kink mode observed in the n = 1 simulations. The overlapping of these modes creates a stochastic magnetic field, leading to stronger EP and bulk plasma pressure redistributions than those observed in the n = 1 simulations. During the nonlinear phase, the transition from the high m = n modes to the low m = n modes is observed where the dominant mode is the m/n=1/1 mode with an internal kink-like structure. These low m = n modes are generated by the nonlinear coupling of the high m = n modes. The EP kinetic effect has a minor contribution to the dynamics of these nonlinearly generated m = n modes.

Optimization of entropy generation and thermal mechanism of MHD hybrid nanoliquid flow in a sinusoidally heated porous cylindrical chamber

The present computational investigation explores the fluid and thermal characteristics along with entropy generation due to buoyancy-driven magnetohydrodynamic (MHD) convective flow of aqueous hybrid nanoliquid filled in a nonuniformly heated porous cylindrical chamber. The fluid motion in the enclosure is modeled by Brinkman — extended Darcy model. The modeled equations are resolved by finite difference approach. The computations are conducted for Rayleigh number (103–105), Hartmann number (0–50), Darcy number (10−5–10−1), different nanoparticle shapes and nanoparticle volume fraction (Ag/MgO: 0–0.05) to understand the characteristic of flow, thermal and irreversibility distribution. With vast numerical simulations, the outcomes reveal that though the buoyancy force is greater, the fluidity cannot be enhanced unless the permeability and magnetic field strength are optimally maintained. As Ra,Ha and Da is varied respectively from 103 to 105, 50 to 0 and 10−5 to 10−1, the fluidity has been enhanced by 99.39%,83.26% and 99.79%. Among all considered parametric combinations, it has been noticed that the choice of Ha=0,Ra=105,Da=10−1 with proper ratio of nanoparticles enhance the system efficiency. However, minimal entropy generation can be achieved with greater Hartmann and lower Darcy numbers. Furthermore, it has been found that blade shaped nanoparticles lead to increase the performance of thermal system.

A passive control of magnetohydrodynamic flow of a blood‐based Casson hybrid nanofluid over a convectively heated bi‐directional stretching surface

AbstractHybrid nanofluids, which are used in nanotechnology, are advanced fluid classes with enriched thermal properties that produce superior outcomes than nanofluids. There are too many applications of hybrid nanofluids in engineering cosmetics, the automotive industry, the home industry, cancer treatment, textiles, paper plastics, paints, and soaps. The purpose of this study is to investigate the heat transfer rate of magnetohydrodynamic flow of Casson hybrid non‐Newtonian nanofluid across an enlarging surface. The current work focuses on magnetohydrodynamic hybrid nanoliquid flow across an extending 3‐D sheet. Additionally, zero mass flux and an adequate convective heating procedure are used as boundary conditions in this investigation. Blood serves as the base fluid, into which copper and alumina nanoparticles are dissolved to form a hybrid nanofluid. Adjusting the applicable similarity transformation, the present modeled equations are converted into dimensionless form. The Homotopy analysis approach (HAM) computes the resulting systems and illustrates them graphically to explain the flow behavior at the extending electrically conducting surface. Additionally, for changes in the non‐dimensional physical constraint values, the variations in physical quantities such as the skin friction, temperature, Nusselt number and velocity profiles are explained. The results of the current investigation demonstrated that a magnetic field and a non‐Newtonian parameter reduce the hybrid nanoliquid's velocity. The temperature profile goes up with thermophoresis and Brownian motion. The component of velocity is found to fall as the stretching ratio parameter rises, while the component of velocity in the direction experiences the opposite impact. When the parameters of a chemical reaction are adjusted upwards, the concentration profile deteriorates. It is originated that the rate at which heat is transferred by hybrid nanofluids is significantly more progressive than that of nanofluids.

An influence of radiation and magnetohydrodynamic flow of hybrid nanofluid past a stretching/shrinking sheet with mass transpiration

AbstractThis research focuses on energy convention and mass transpiration in magnetohydrodynamic hybrid nanofluid (Al2O3–Cu) flows driven by a moving surface, which build numerous applications such as inducing hypothermia in cancer tumors, reducing bleeding in severe injuries, and performing magnetic resonance imaging are only a few medical applications applying magnetohydrodynamics A similarity transformation describes the representational construction of the steady two‐dimensional nonlinear partial differential equations (PDEs) to a set of nonlinear ordinary differential equations (ODEs). Above equations subject to corresponding boundary conditions are analytically solved. Specifically, the energy equation with radiation effect is solved analytically using incomplete Gamma function. Moreover, the graphs included physical representations of the measurement can be found in this paper. In summary, our findings demonstrate that mass‐transfer induced slip has a non‐negligible impact on flows driven by a moving sheet. Mass transfer induced slip may even be able to dominate the flow driven effect of the moving sheet by changing the flow directions to flow against the sheet motion and also thermal radiation parameter increases as thermal boundary layer increases.

Entropy Generation in a Magnetohydrodynamic Hybrid Nanofluid Flow over a Nonlinear Permeable Surface with Velocity Slip Effect

The current study is designed to model the hydrothermal feature of a hybrid nano liquid slip flows over a permeable expanding/contracting surface with entropy generation. The model incorporates Cu-Al2O3 nanoparticles with water as the host liquid to simulate the flow. Additional impacts incorporated into the novelty of the model are viscous dissipation and Joule heating. The model is transformed appropriately to its dimensionless form using similarity quantities and the solution is numerically obtained using the spectral quasi-linearization method (SQLM). The impact of pertinent factors on the flow characteristics is communicated through graphs for the hybrid nano-suspension to discuss the hydrothermal variations. The friction factor and the rate of heat transport are also discussed with sensible judgment through tables. To ensure the code validity, a comparison with earlier studies is conducted and excellent consensus is accomplished. The result explored that diminution in the irreversibility ratio is witnessed for rising magnetic field strength along the free stream, distance away from the permeable surface as the heat dissipation to the surrounding decelerates. Also, the augmented nonlinearity parameter intensified the heat transfer rate for about 2.79% of the hybrid nano-suspension.

Dual solutions for magnetic-convective-quadratic radiative MoS2 − SiO2/H2O hybrid nanofluid flow in Darcy-Fochheimer porous medium in presence of second-order slip velocity through a permeable shrinking surface: Entropy and stability analysis

ABSTRACT This investigation aims to scrutinize the flow phenomenon and thermal variations of magnetohydrodynamic hybrid nanofluid flow induced by a shrinking surface. The novelty of the work is to examine the flow and heat transport behavior with entropy production of mixed convective / hybrid nanofluid through a Darcy–Forchheimer porous medium in the presence of nonlinear quadratic thermal radiation with second-order velocity slip over a contracting surface. Nanoparticles molybdenum disulfide and silicon dioxide are coupled with the base fluid water () to construct / hybrid nanofluid. The governing set of nonlinear partial differential equations with corresponding boundary constraints is converted into a set of nonlinear ordinary differential equations using the similarities transformation before being solved numerically with the help of the default solver in the MATLAB bvp4c package. A dual solution is determined based on the emerging parameters, including a certain amount of mass suction parameter, nanoparticle volume fractions, magnetic field, Grashof number, nonlinear quadratic thermal radiation, Darcy–Forchheimer factor, and first- and second-order velocity slip factors, for the velocity, temperature, skin friction, and local Nusselt number, and they are analyzed tabularly and graphically. These results also indicate that the solution for the upper branch was stable, while it was unstable for the lower branch based on the stability analysis. Quadratic thermal radiation has been discovered to considerably impact the fluid’s temperature and the pace of heat transfer. The magnetic field resistance and Forchheimer number slow the flow of the liquid and increase its temperature. Furthermore, by combining silicon oxide with a volume percentage of molybdenum disulfide, the flow is retarded, and heat transfer is enhanced. With an increase in the nanoparticle volume fraction by , the skin friction is boosted up by almost and and local Nusselt number is decelerated by almost , for a particular upper branch over the shrinking surface due to the influences of and nanoparticles, respectively. Furthermore, quadratic thermal radiation and first-second-order velocity slip considerably enhance the entropy formation.

Numerical investigation of the magnetohydrodynamic hybrid nanofluid flow over a stretching surface with mixed convection: A case of strong suction

The present work explores the physical aspects of the alumina and silver nanoparticles on the magnetohydrodynamic (MHD) flow of mixed convection micropolar hybrid nanofluid with ethylene glycol + water [Formula: see text] base fluid via stretching surface embedded in a porous medium. A strong magnetic field is employed normally in the flow direction. The behavior of the suction on the presented flow analysis is discussed strongly. Heat transport phenomena are analyzed. The current model’s mathematical modeling is based on higher-order nonlinear partial differential equations, which are then translated into higher-order nonlinear ordinary differential equations using appropriate similarity transformations. The modeled higher-order nonlinear ordinary differential equations are solved using NDSolve technique. The physical significance of the different flow parameters on the velocity, microrotation, and temperature profiles of the hybrid nanofluid are described in a graphical form. In a tabular form, the skin friction coefficients for nanofluid and hybrid nanofluid against various flow parameters are calculated. Some important results from this investigation are demonstrated that the velocity of the hybrid nanofluid is higher for the stretching ratio parameter and it is detected that the suction parameter enhanced the microrotation profile of the hybrid nanofluid. From the comparison, it is noted that the velocity, microrotation, and temperature of the hybrid nanofluid are higher as compared to the velocity, microrotation, and temperature of the alumina nanofluid and silver-nanofluid.

Corrigendum: Analysis of the electrically conducting magnetohydrodynamic hybrid nanofluid flow past a convectively heated stretching surface with suction/injection and non-linear thermal radiation

Corrigendum: Analysis of the electrically conducting magnetohydrodynamic hybrid nanofluid flow past a convectively heated stretching surface with suction/injection and non-linear thermal radiation

Analysis of the electrically conducting magnetohydrodynamic hybrid nanofluid flow past a convectively heated stretching surface with suction/injection and non-linear thermal radiation

Fluid flow through a porous media has many industrial applications such as water flowing through rocks and soil and purification of gas and oil mixed in rocks. Also, heat transfer enhancement has been introduced in various thermal and mechanical systems by improving the thermal conductance of base fluids. In this article, the flow of an electrically conducting water-based hybrid nanofluid comprising GO and Fe3O4 nanoparticles over an extending sheet using a porous medium has been investigated. The space-dependent heat source, Joule heating, Brownian motion, thermophoresis, thermal radiation, chemical reaction, and activation energy impacts are taken into account. For the solution of the modeled equations, the homotopy analysis method is considered. The homotopic convergence is shown with the help of a figure. This analysis is contrasted with previous outcomes and has found a great agreement. The impacts of embedded factors on different flow characteristics, skin friction coefficient, and Nusselt and Sherwood numbers are displayed using figures and tables. The outcomes of the present analysis show that the increasing magnetic and suction factors have reduced the fluid motion while amplifying the thermal profiles. Additionally, the suction factor has a reducing impact on both temperature and concentration profiles. The thermal profiles have increased with the increasing thermal Biot number, Eckert number, thermophoresis, and Brownian motion factors. The Nusselt numbers have increased with the increasing thermal Biot number and stretching factor but reduced with the increasing thermal radiation and temperature difference factors.

Buoyancy-driven flow of magnetohydrodynamic hybrid nanofluids in an open cavity with permeable horizontal walls

The buoyancy-driven flow of hybrid nanofluids in an open cavity is examined in the presence of a magnetic field with an angle to the horizontal axis. The right end of the cavity is open, and the left wall is supposed to be heated. Moreover, the horizontal walls are deemed to be permeable and maintained at ambient temperature. The successive over-relaxation (SOR) technique is applied with the finite-difference method to solve the dimensionless equations. A comparison is executed with formerly published results which provide a good agreement. The grid refinement test has also been carried out to increase the accuracy. Flow and temperature profiles are investigated for the Rayleigh number ( Ra = 104, 105, 106), Reynolds number (Re = 5, 8, 10, 20, 100), Hartmann number ( Ha = 0, 5, 10), concentration of nanoparticles ( φ1 or φ2 = 0.0, 0.05, 0.1), angle of inclination of the magnetic field ( γ = 0°, 30°, 45°), aspect ratio ( A = 1, 2, 3, 4), and suction/blow parameter ( S = −1, 0, 1). Results have been elucidated based on streamlines, isotherms, local Nusselt number ( Nu), and average Nusselt number ( Nuavg). It is noted that the changes in the variables significantly affect streamlines and isotherms. The heat transfer for Cu-Fe3O4/water hybrid nanofluid is higher about 9.98% compared to Fe3O4/water nanofluid and 26.41% compared to water. Furthermore, all other parameters noticeably augment both Nu and Nuavg.

Second-order slip flow of a magnetohydrodynamic hybrid nanofluid past a bi-directional stretching surface with thermal convective and zero mass flux conditions

The nanoliquid concept has variety of applications toward biomedicine, heat exchangers, cooling of electrical devices, foods, and transportation. It is important to add various kinds of solid nanoparticles, such as silica, copper, silver, alumina, graphene, gold, and so on to the base fluids to increase the thermal efficiency of common fluids like engine oil, kerosene oil, water, sodium alginate, etc. This research explores the second-order slip flow of a Cu-Fe3O4/H2O past a bi-directional stretching surface. The current research takes into account the conditions of thermal convection, zero mass flux, and velocity slips. It is important to note that the hybrid nanoliquid flow’s wall mass transfer rate is eliminated by the zero mass flux at the wall. Furthermore, a strong magnetic field, thermophoresis, activation energy, exponential heating, chemical reaction, and Brownian motion are also studied. The mathematical framework of this report is presented in the form of PDEs which are then converted into ODEs via appropriate similarity transformations. A semi-analytical method called HAM, is used in order to solve the transformed ODEs. The convergence of HAM is shown with the help of Table. The impacts of physical parameters on the flow distributions are shown with the help of Tables and Figures. The findings of this study demonstrate that the velocity distributions of the hybrid nanofluid flow are decreased as the magnetic constraint is augmented. The ratio parameter has an inverse relationship to the primary velocity and has direct relationship to the secondary velocity. The energy profile has augmented due to the higher thermal Biot number. The present analysis is validated by comparing the new results with reported results.

Magnetohydrodynamic hybrid nanofluid flow over a decelerating rotating disk with Soret and Dufour effects

PurposeThe investigation of fluid flow over a rotating disk has been increasing due to the spread of machine technology. Because of this development, we scrutinized the Magnetohydrodynamic (MHD) flow of hybrid nanofluid caused by a decelerating rotating disk with Ohmic heating, Soret and Dufour effects. The disk's angular velocity is taken to be an inversely time-dependent linear function. Moreover, the temperature-dependent viscosity of hybrid nanofluid is incorporated in the present investigation. Methanol is considered as base fluid, while copper oxide (CuO) and magnesium oxide (MgO) are nanoparticles.Design/methodology/approachEstimated fundamental partial differential equations of flow problems are altered as a dimensionless system of ordinary differential equations using appropriate similarity transformation and solved using a numerical technique: BVP Midrich scheme in Maple software. The impression of emerging non-dimensional parameters is portrayed graphically. All outcomes are shown in the velocity, temperature and concentration profiles.FindingsThe developed flow problem involves a non-dimensional parameter (A) that reveals the deceleration of the disk. For larger values of A, the disk decelerates faster and for some fixed time, the fluid surrounding the disk revolves more rapidly than the disk itself. The radial velocity of fluid diminishes and axial velocity becomes uniform when the disk is subjected to wall suction velocity (B).Originality/valueThis analysis is significant in biomedical engineering, cancer therapeutic, manufacturing industries and nano-drug suspension in pharmaceuticals. The novelty of the current study is the hybrid nanofluid flow with Ohmic heating, Soret and Dufour effects on a decelerating rotating disk. To the best of the author's knowledge, no such consideration has been published in the literature.

Numerical simulations of fishbones driven by fast ions in negative triangularity tokamak

The discharges with negative triangularity have lower turbulence induced transport and better energy confinement, so the tokamak with negative triangularity is recognized to be a better choice for future fusion device. In order to explore the features of the energetic particle driven instabilities with negative triangularity, the kinetic-magnetohydrodynamic hybrid code M3D-K is used to investigate the linear instability and nonlinear evolution of the fishbone driven by energetic ions with different triangularity. Based on EAST-like parameters, it is found that the negative triangularity destabilizes the ideal internal kink mode, but stabilizes the fishbone instability. Nonlinear simulations show that the fishbone instability with negative triangularity is hard to saturate without fluid nonlinearity. The possible explanation is that the orbits of fast ions are located more centrally with negative triagularity, so the energy exchange between energetic ions and the fishbone is more efficient than that with positive triangularity. These simulation results demonstrate that the negative triangularity does not have an obvious advantage over the positive triangularity, with the fishbone driven by energetic particles considered.

Heat transport and magnetohydrodynamic hybrid micropolar ferrofluid flow over a non-linearly stretching sheet

<abstract> <p>A stable colloid called ferrofluid is made up of tiny magnetic particles, often magnetite (Fe<sub>3</sub>O<sub>4</sub>), that have been bonded with an amphiphilic dispersion layer and are then suspended in a suitable liquid solvent carrier. Current industrial uses for ferrofluid include dynamic sealing, inertial and viscous damping, magnetic drug targeting, liquid microrobots, etc. In this article, we studied the heat transfer and MHD micropolar ferrofluid flow caused by non-linearly stretching surface. The results are presented for hybrid alumina- copper/ethylene glycol (${Al}_2 {O}_3$-Cu/EG) nanofluid. The governing non-linear equations describing flow are transformed into a system of ordinary differential equations using similarity transformations. Using the BVp4c method, the microstructure and inertial properties of a magnetite ferrofluid across a non-linear stretched sheet are studied. The influence of relevant parameters on stream function, velocity, micro-rotation velocity, and temperature are obtained and represented graphically. The computed results are original, and it has been observed that if we increase the magnetic parameter, the stream function and the velocity decrease, while the temperature and micro-rotation velocity increase. As the Prandtl number increases, the temperature profile decreases. It has been observed that the Nusselt number or heat transfer rate of hybrid nanofluid is better as compared to nanofluid flow.</p> </abstract>

Steady Magnetohydrodynamic Flow of Cu–Al2O3/Water Hybrid Nanofluid Over a Yawed Cylinder

This study presents non-similar solutions for the magnetohydrodynamic hybrid nanofluid copper-alumina/water flow over an infinite yawed cylinder, featuring an emphasis on entropy generation owing to heat transfer, fluid friction, and joule heating. Non-similar transformations are used to convert non-linear governing equations and boundary conditions into a non-dimensional form, which is subsequently linearized using the quasi-linearization approach. Implicit finite differentiation is used to solve the equations that arise. The influence of viscous dissipation is considered and entropy generation analysis is done for various values of yaw angle, magnetohydrodynamic parameter and viscous dissipation parameter. The results show that when the magnetic field is increased, the ordinary separation is delayed. The thermal boundary layer of the hybrid nanofluid copper-alumina/water is found to be thicker than the thermal boundary layer of the nanofluids copper/water and alumina/water as well as the working fluid water. As the viscous dissipation and magnetic field increase, the overall entropy generation increases. To lower overall entropy generation, the cylinder’s yaw angle must be increased.

Mixed convection MHD hybrid nanofluid over a shrinking permeable inclined plate with thermal radiation effect

In many applications, hybrid nanofluids showed superior heat transfer outcomes; nevertheless, further study is needed to expand the range of applications for hybrid nanofluids. Therefore, in this study, the radiative magnetohydrodynamic (MHD) mixed convective alumina-copper/water hybrid nanofluid flow past an inclined shrinking plate is analyzed. By incorporating similarity transformations, the PDEs of the flow model is converted to ODEs. The boundary value problem of the fourth-order accuracy code (bvp4c) is implemented to solve the mathematical model numerically. When preliminary assumptions are appropriate, the above-proposed method may provide non-unique outcomes. Due to the plate’s shrinking motion, two solutions are possible. The first solution is stable based on a stability study. Therefore, we only rely on the first solution for effective practical uses. The findings reported that using less copper concentration (1 % volume fraction instead of 2 %) and applying more thermal radiation and MHD effect, the heat transfer rate might increase significantly when the plate is inclined considerably (at 70 degrees). It is possible to avoid the flow separation by upsurging the copper volume fraction from 1 % to 2 % at a higher MHD effect. The boundary layer separation is not affected by the employment of various inclination angles, variable thermal radiation, and mixed convection. This study offers valuable insight into fundamental transport phenomena such as the transmission of heat, momentum, or mass. Thus, it provides valuable information on the gradients of essential factors to control the boundary layer flow pattern.

Numerical Analysis of Hybrid Nanofluid Flow Over a Nonlinear Stretching Sheet with Viscous Dissipation, Joule Heating Effects

The main objective of this article is to explore magnetohydrodynamic hybrid nanofluid flow past a stretching sheet. Mathematical model is developed by revisiting the work done by previous study and extended the same model for hybrid nanofluid flow scenario with viscous dissipation, joule heating and thermal radiation effects. Choosing appropriate similarity variables governing equations are transformed into system of ordinary differential equation and thereby solved by using shooting mechanism. Impact of various physical parameters on momentum, temperature and concentration profiles are shown through graphs. Important engineering quantities like skin friction coefficient, Nusselt number etc. are computed and discussed. In order to verify the code, the computed results are compared with existing literature and acceptable convergence notified in obtained results. Comparative analysis for mono particle nanofluid and hybrid nanofluid is explained for all flow parameters.

Heat and Mass Transport Analysis of MHD Rotating Hybrid Nanofluids Conveying Silver and Molybdenum Di-Sulfide Nano-Particles under Effect of Linear and Non-Linear Radiation

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.

Magnetohydrodynamic hybrid nanofluid flow with the effect of Darcy–Forchheimer theory and slip conditions over an exponential stretchable sheet

The characteristics of water-based hybrid nanofluid flow when passing over an exponentially stretchable sheet with velocity and thermal slip factors are presented. This article provides a concept for a hybridized fluid comprising copper and cobalt iron oxide nanoparticles (NPs) dispersed into a base fluid (water). In addition, physical observations of the heat absorption behavior, the Darcy effect, the thermal radiation, and viscous dissipation are also taken into account. Because of their strong thermophysical properties, copper and cobalt iron oxide NPs are used in a wide range of applications in the engineering and medical fields. To study the dynamics of these NPs, a system of partial differential equations (PDEs) has been generated that forms a highly nonlinear coupled model. The PDE system is converted into nondimensional ordinary differential equations (ODEs) with the aid of similarity replacements. The semi-analytical homotopy analysis method (HAM) is applied to the set of dimensionless ODEs obtained to find the solution. Two engineering parameters, the Nusselt number and the skin friction, are plotted versus various parameters of the hybridized fluid using bar charts. It was observed that the no-slip condition, the suction parameter, and the Darcy–Forchheimer medium enhanced the thermal profile of the hybridized fluid.

Unsteady flow of magnetohydrodynamic hybrid nanofluid over a stretching/shrinking sheet: Multiple solutions

The main goal of this article is to perform a heat transfer analysis of unsteady magnetohydrodynamic hybrid nanofluid flow over a stretching/shrinking sheet. The hybrid nanofluid is synthesized by adding two kinds of nano-sized particles. In this examination, TiO2 and Cu nano-sized particles are taken with water as a base fluid. Using an appropriate similarity transformation approach, a set of nonlinear equations is obtained from the governing equations of the current study. To solve the changed system, the Runge–Kutta–Fehlberg approach is applied combined with the shooting method. The obtained data is presented in graphs and tables. Here, dual solutions can be seen utilizing upper and lower division solutions particularly aimed at a specific domain of unsteadiness parameter. The skin friction coefficient parameter shows a considerable improvement. Whereas in the case of the shrinking sheet, larger values of the magnetic parameter and solid volume fraction results in a significant drop in the local heat transfer rate for the upper branch case, while the lower branch case shows a different pattern.