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This study implements the comparative study of Casson and Williamson nanofluids by considering the impacts of linear thermal radiation and inclined magnetohydrodynamics. Here, we employ graphs to compare the variables affecting the behavior of non‐Newtonian and Newtonian fluids for a range of physical and dimensionless parameter values. The flow's coupled equations, which contain multiple independent variables, these equations can then be changed into a single independent variable by adding similarity variables and can be solved by applying the shooting method. The effects of thermomigration and Brownian motion on nonlinear flow equations are graphically examined. For an array of radiation parameter values, we have observed that the Newtonian fluid's concentration is lesser than that of both the non‐Newtonian fluids and also noticed that Newtonian fluids converge a little sooner than Casson and Williamson fluids. The primary innovation is shown in Table 1, where the mass transfer and heat transfer values are contrasted with the limiting circumstances of previous research findings that are documented in the literature. [ABSTRACT FROM AUTHOR]

In the current work, slip and radial magnetic field effects are taken into consideration as they relate to a comparison examination regarding two-dimensional heat transfer caused on the basis of the free convective flow of a Casson (non-Newtonian) fluid in electro-conductive and non-Darcy porous medium of a horizontal circular cylinder. The formulation has been created, and the boundary layer equations are then transformed using similarity transformations into a self-similar form. Using the Keller box method (KBM), a nonlinear boundary value that is simplified issue is numerically resolved, the momentum and temperature equations, higher-order partial differential equation to first-order partial differential equation. Graphs are used to show the numerical solutions for Nusselt number, skin friction coefficient, velocity profile, and temperature profile. With graphs and tables, the impact of key variables, rate of heat transfer, and skin irritation are measured. The flow of the fluid is the most interesting aspect of the analysis; the outcome shows that Casson fluid velocity fields are reduced by an increase in magnetic number and nonuniform heat source/sink, radiation parameter, and when it comes to magnetic number variation. Increase in magnetic body force parameter (H) values results in decreases in the component of velocity. Skin friction coefficient and Nusselt number rise at high Newtonian slip (SF), non-Darcy parameter (Da), and Prandtl number (Pr) values. [ABSTRACT FROM AUTHOR]

Application: The impact of flow, heat transfer, and magneto hydrodynamics on sensor surfaces between two parallel compressing plates with porous walls has been examined in this study. This study focuses on understanding unsteady compressed flow in two dimensions, utilizing Aluminum oxide, copper oxide, and titanium dioxide with base fluid polymers as the base fluid. Nanofluids, known as nanometer suspensions in traditional nanoscale fluid transfer, are explored for their potential application in improving lubricative and cooling properties. Purpose and methodology: This study aims to investigate the behavior of a tri-hybrid nanofluid (Aluminum oxide, copper oxide, and titanium dioxide with base fluid polymers) in terms of flow dynamics, heat transfer, and magneto hydrodynamics. Energy and momentum equations, considering magneto hydrodynamic forms and heat transfer, are analyzed. The study employs numerical methods, including similarity transforms and a shooting approach, to solve the governing equations. Core findings: Several parameters, including permeable parameter, magnetic parameter, squeeze flow index parameter, volume fraction by nanoparticles, and radiation parameter, are investigated for their effects on temperature profile and velocity profile. The study illustrates these effects graphically and discusses the influence of these parameters on different components of velocity and temperature fields. Additionally, the impact of the radiation parameter (R) on temperature fields is examined for both positive. Future work: Future research may focus on further optimizing the tri-hybrid nanofluid composition for specific applications, exploring additional parameters that may affect flow behavior, heat transfer, and entropy generation. Additionally, experimental validation of the numerical findings and the development of more advanced numerical techniques for solving complex fluid dynamics problems could be the areas of interest for future work. [ABSTRACT FROM AUTHOR]

AbstractThe aim of this study is to examine the results of MHD, radiation and Casson ternary fluid over a horizontal cylinder with a saturated porous medium. The nanofluids used in this study are trihybrid, consisting of Cu, Al2O3 and Tio2 particles suspended in blood as the base fluid. The dimensional form of governing equations is transformed into dimensionless form by manipulating non-similar solutions. The conservation equations are solved using the Keller Box Method (KBM). The presence of several emerging dimensionless parameters, namely the Casson fluid parameter (β), Darcy number (Da), Forchheimer parameter (∧), radiation parameter (Rd) and magnetic field (M) on fluid momentum and energy changes in the boundary layer regime are investigated in detail. The Prandtl value (Pr) for blood is determined to be 21. The application of porous medium models spans across various fields, including engineering, environmental science, biology, and materials science. [ABSTRACT FROM AUTHOR]

The primary aim of the study is to offer a precise analysis of the impact of the radiation parameter and Soret number on the magneto hydrodynamic (MHD) free convective flow of an incompressible, electrically conducting viscous fluid (IECVF) over an inclined plate immersed in a porous material (IPIPM). The impulsively started plate with changing mass diffusion and temperature is taken into account. Perturbation technique is applied to solve the non-dimensional momentum equation along with the energy diffusion and mass diffusion equations. Equations are found for the fields of velocity (u), temperature (θ) and concentration (φ). Expressions are obtained for skin friction (SF), Nusselt number (Nu) and Sherwood number (Sh). The graphical representations of the outcomes of various parameters on 'u, 'θ', and 'φ' and on SF, Nu and Sh are drawn, to highlight their effects. [ABSTRACT FROM AUTHOR]

With the growing interest in radiant heating and cooling systems, driven by their improved efficiency and enhanced thermal comfort compared to air systems, there is an increasing need to develop a more accessible method for designers to understand the implications of radiation heat exchange between the human body and radiant panels. To address this, a novel angle factor calculation model, named the HNU Angle Factor Model, was developed, taking into account the spatial arrangement and geometric relationship between the human body and radiant panels. The angle factors obtained using the HNU Angle Factor Model exhibited good agreement with the results obtained with Fanger diagrams and the contour integral method, with average relative differences of 8.1% and 10.0% for 140 cases, respectively. Furthermore, placing a radiant panel on the floor while maintaining its fixed size can contribute to the creation of an even and efficient thermal environment for individuals in both seated and standing positions. By implementing the HNU Angle Factor Model in practical engineering applications, more effective utilization of radiant systems can be achieved, as it provides an evaluation of the heat transfer between the human body and radiant panels. [ABSTRACT FROM AUTHOR]

The present work investigates Reiner–Rivlin fluid's movement on a stretching surface with an inclined magnetic field, thermal radiation, and slip impacts. The governing equations are modeled with suitable assumptions. The governing equations are transformed into ordinary differential equations with suitable similarity terms. The numerical results are computed with the help of Runge-Kutta-Fehlberg 4th 5th order (RKF-45) and the shooting technique. The results are discussed in detail with the help of tables and graphs. The analysis mainly focuses on the different inclined angle impact over velocity and thermal profiles. The outcome reveals that the maximum thermal distribution and minimum velocity are seen with an inclined angle ξ = 90 ∘ . The cross-viscosity parameter directly impacts the velocity profile but shows a reverse trend on the thermal profile. The surface drag force is found to be minimum ξ = 90 ∘ followed by ξ = 45 ∘ and ξ = 0 ∘ . The thermal distribution rate is observed maximum at ξ = 90 ∘ than ξ = 45 ∘ and ξ = 0 ∘ . [ABSTRACT FROM AUTHOR]

This study focuses on investigating the energy and mass transfer characteristics of a hybrid nanofluid by comparing its performance with that of the base fluid using the finite difference method. Viscous dissipation, thermal radiation, Newtonian heating conditions, and radiation, along with MHD, are considered on the infinite vertical plate for framing the governing equations. The finite difference technique is employed to numerically solve the governing equations of heat transfer in a computational domain. The key goal of this research is to evaluate the effect of nanoparticle concentration, size, and thermal conductivity on the energy transfer characteristics of the hybrid nanofluid. To accomplish this, a comprehensive parametric analysis is conducted, considering various combinations of nanoparticle volume fractions, sizes, and thermal conductivities. The performance of the hybrid nanofluid is then compared to that of the base fluid to assess the potential enhancements in heat transfer. The solution of the study provides valuable insights into the heat transfer behavior of the hybrid nanofluid and its comparison with the base fluid. The findings demonstrate the impact of nanoparticle properties on energy transfer enhancement and reveal the optimum conditions for achieving improved thermal performance. Moreover, the study highlights the limitations and challenges associated with the use of hybrid nanofluids in practical applications, facilitating informed decision-making for their effective utilisation. [ABSTRACT FROM AUTHOR]

This work examines the boundary flow difficulties of the past and the heat transfer properties of Blasius and Sakiadis flows under prescribed concentration flux and prescribed heat flux. The nanofluid is also taken into account in this model, along with impacts from Brownian motion and thermophoresis. The modified system governing partial differential equations is numerically solved by using the R‐K method along with the shooting technique. Various values of physical quantities like thermophoresis parameter, Brownian motion parameter, Eckert number, thermal radiation parameter, heat source parameter, and magnetic field parameter along with the Cf, Nux, and Shx ${C}_{f},\unicode{x02007}N{u}_{x}\,,\unicode{x02007}\text{and}\unicode{x02007}S{h}_{x}$ were calculated using the temperature, concentration, and velocity profiles. Finally, we demonstrated how the Brownian motion, radiation, and thermophoresis parameters can significantly increase the temperature distributions. The concentration distributions were decelerated with an increase in Brownian motion parameters for both Blasius and Sakiadis cases. [ABSTRACT FROM AUTHOR]

The current research analyzes Soret and Dufour effects on magneto hydrodynamic natural convection viscous-elastic radiative Casson fluid flow across a non-linear stretchy sheet. First, the PDEs (partial differential equations) are changed using similarity analysis into non-linear paired ODEs (ordinary differential equations). Then, using the BVP4C technique, ordinary differential equations are numerically solved. Engineering interest of substantial quantities like skin-friction coefficient, Nusselt parameter, and Sherwood parameter debated in the table with multiple significant characteristics. The current study describes that the temperature profile increases with rising thermal radiation and the Dufour effect. A declining Sherwood impression of Soret number is depicts in current study. An increasing radiation impact declines the Nusselt number. In addition, the concentration field enhances due to an increasing Soret effect. [ABSTRACT FROM AUTHOR]

With the growing interest in radiant heating and cooling systems, driven by their improved efficiency and enhanced thermal comfort compared to air systems, there is an increasing need to develop a more accessible method for designers to understand the implications of radiation heat exchange between the human body and radiant panels. To address this, a novel angle factor calculation model, named the HNU Angle Factor Model, was developed, taking into account the spatial arrangement and geometric relationship between the human body and radiant panels. The angle factors obtained using the HNU Angle Factor Model exhibited good agreement with the results obtained with Fanger diagrams and the contour integral method, with average relative differences of 8.1% and 10.0% for 140 cases, respectively. Furthermore, placing a radiant panel on the floor while maintaining its fixed size can contribute to the creation of an even and efficient thermal environment for individuals in both seated and standing positions. By implementing the HNU Angle Factor Model in practical engineering applications, more effective utilization of radiant systems can be achieved, as it provides an evaluation of the heat transfer between the human body and radiant panels.

In this article, we have discussed in detail the effect of Newtonian heating on MHD unsteady free convection boundary layer flow past an oscillating vertical porous plate embedded in a porous medium with thermal radiation, chemical reaction and heat absorption. The governing PDEs of the model together with related initial and boundary conditions have been solved numerically by the finite element method. The dimensionless velocity, temperature and concentration profiles are analyzed graphically due to the effects of key parameters in the concerned model problem. Computed results for the skin friction coefficient, Nusselt number and Sherwood number are put in tabular form. It is observed that the thermal and mass buoyancy effects support the velocity whilst a reverse effect is noticed when the strength of the magnetic field is increased. The velocity and temperature enhances with an increase in the Newtonian heating and thermal radiation whilst a reverse effect is observed with an increase in the Prandtl number and heat absorption parameter. Increasing Schmidt number and chemical reaction parameter tends to depreciate both velocity and concentration. The Newtonian heating, thermal radiation and magnetic field tends to decrease in the skin friction. The Nusselt number increases with increasing Newtonian heating and heat absorption parameters. An increase in the Schmidt number and chemical reaction rate tends to improve the Sherwood number.

This paper explores the time-dependent magnetohydrodynamics (MHD) micropolar fluid flow over a three-dimensional variable stretching surface in the occurrence of radiation effect. The model time-dependent partial differential equations (PDE's) in three independent variables are transformed into ordinary differential equations (ODE's) by the suitable self-similarity variables. Homotopy perturbation method (HPM) and Runge-Kutta (RK) 4th order method along with shooting technique are used in the present model. And also, HPM results are compared with Runge-Kutta (RK) 4th order method along with the shooting technique. The velocity, micro rotation in x and y directions, temperature, skin friction factor and heat transfer rates are examined for the emerging parameters. The velocity profiles and momentum boundary layer thickness intensification with increasing values of the vortex viscosity parameter. The higher value of a magnetic parameter declines the skin friction coefficient. This type of investigation may be profitable to the polymer fluids, exotic lubricants, electronic chips, artificial fibers, drawing of copper wires, etc.

In this paper, the effects of thermal radiation on unsteady MHD flow viscous incompressible electrically conducting fluid past an impulsively started oscillating vertical plate with variable temperature and constant mass diffusion in the presence of Hall current have been presented. The dimensionless governing partial differential equations of the flow have been solved numerically by using the Galerkin finite element method. The numerical solutions for fluid velocity, angular velocity, temperature, and concentration are represented graphically whereas the numerical results of primary skin friction, rate of heat and mass transfer are presented in tabular form for various parameters involved. The current results were compared to the existing analytical solution based on the Crank–Nicolson implicit finite difference technique. The current study's findings have been shown to be extremely consistent with earlier findings. [ABSTRACT FROM AUTHOR]

The present work discloses the magnetohydrodynamic pulsating flow of blood-carrying A l 2 O 3 nanoparticles in a channel with the viscous dissipation and Joule heating effects. Couple stress fluid is treated as blood which is the base fluid. The Maxwell Garnett model for thermal conductivity of nanofluid is considered. The thermal radiation and heat source/sink impacts are taken into account. Analytical expressions for dimensionless flow variables are obtained by employing the perturbation method. The impact of active parameters on flow variables is graphically presented. The obtained results show that the velocity of nanofluid increases with an increment in frequency parameter, whereas it decreases for a rise in Hartmann number, nanoparticles volume fraction and couple stress parameter. There is an enhancement in temperature of nanofluid with increasing viscous dissipation, whereas there is a decrease in temperature with an increase in the applied magnetic field. The Nusselt number rises with an enhancement in volume fraction of nanoparticles and Hartmann number at both the walls. Further, the validity of present results is assured by the comparison of analytical and numerical outcomes with an excellent harmony. [ABSTRACT FROM AUTHOR]

• HNF flow and heat transfer over stretching/shrinking sheet for unsteady case is studied. • The analytical solutions are obtained for velocity and temperature in terms of exponential. • The conditions of upper branch and lower branch solutions are obtained. • The velocity boundary layer thickness is less for more value of V C. • Radiation number increases the thermal boundary-layer thickness. The inclined magnetohydrodynamic (MHD) unsteady flow and heat transfer of Casson hybrid nanofluid (HNF) due to porous stretching sheet is investigated. In the present paper we analyze the Casson fluid unsteady flow over permeable flat plate in the presence of inclined magnetic field and heat transfer of fluid with the effect of thermal radiation. The conservation of mass, conservation of momentum and thermal equations are non-dimensional into the system of nonlinear ODEs by taking the suitable similarity transformation. An exact analytical solution is obtained for velocity. The energy equation in the presence of inclined magnetic field and radiation is a differential equation with variable coefficients, which is transformed to an incomplete gamma function using a new variable and using the Rosseland approximation for the radiation. The governing differential equations are solved analytically and the effects of various parameters on velocity profiles, skin friction coefficient, temperature profile and wall heat transfer are presented graphically. There is an enhancement in heat transfer and pressure drop by usage of HNF. The variations in velocity and temperature profiles with respect to different various pertinent physical parameters. An increase of the mass transpiration (suction) parameter intensity increases the skin friction, which consequently improves the heat transfer enhancement and reduces the HNF temperature. Furthermore, the skin friction coefficient increases due to mass suction and MHD in the stretching sheet, whereas the rate of heat transfer decays. The results have possible technological applications in liquid-based systems involving stretchable materials. [Display omitted] [ABSTRACT FROM AUTHOR]

The effects of chemical reaction on a transient MHD mixed convection flow with mass transfer past an impulsively fixed infinite vertical plate under the influence of a transverse magnetic field have been presented. The medium is considered to be non-scattering and the fluid to be non-gray having emitting-absorbing and optically thick radiation limit properties. The dimensionless governing equations of the flow and mass transfer with boundary conditions are solved numerically by using the Ritz finite element method. The numerical results for the velocity, temperature and the concentration profiles as well as the skin-friction coefficient for different values of physical parameters such as the radiation parameter, magnetic parameter, Schmidt number and chemical reaction parameter have been obtained and presented through graphs and tables. It has been found that there is a fall in the temperature and velocity for both air and water as the radiation parameter is increased. An increase in the Schmidt number and chemical reaction parameter results a decrease in the concentration and velocity profiles for both air and water. Furthermore, an increase in the radiation parameter, magnetic parameter, Schmidt number and chemical reaction parameter decreases the skin-friction.

The numerical investigation of the effects of radiation and chemical reaction on an unsteady MHD free convection flow with a parabolic starting motion of an infinite isothermal vertical porous plate taking into account the viscous dissipation effect has been carried out. The fluid is considered a gray, absorbing emitting radiation but a non-scattering medium. The dimensionless governing equations for this investigation are solved numerically by applying the Ritz finite element method. Numerical results for the velocity profiles, temperature profiles and concentration profiles as well as the skin-friction are presented through graphs and tables for different values of the physical parameters involved. Results obtained show a decrease in the temperature and velocity in the boundary layer as the radiation parameter increased. The velocity increases with an increase in the thermal and mass Grashof numbers and decreases with an increase in the magnetic parameter. Further, the concentration and velocity decreases with increasing the Schmidt number and chemical reaction parameter. These findings are in very good agreement with the studies reported earlier.

The central stimuli of this brief note is to underscore the effect of the temperature dependent convection coefficient that give rise to a dual temperature regime facilitating dual entropy distribution. In order to avoid unwarranted complexities, a simple geometry of shear flow in a channel is considered. The energy equation amenable to an analytic solution is simulated to extract the desired numerical findings in as much as for what parameters' values, the temperature has dual distribution/does not yield temperature distribution at all. In fact, a range of parameter values have been worked out for which dual temperature regime exists or not. The plots of entropy generation number Ns also show the dual regime. The findings reveal a qualitative and quantitative difference in dual systems of temperature and entropy. It further underlines that the thermal systems with the idealized uniform heat transfer coefficient may be far distinct from actual behaviour and even weak temperature dependence of convection coefficient need due attention while designing a system. [ABSTRACT FROM AUTHOR]

Abstract Latent Heat Thermal Energy Storage Systems (LHTESS) can be employed to store large amount of energy. Present research deals with solidification process of Hybrid nano-enhanced Phase Change Material (HNEPCM) in a thermal storage system with Koch snowflake inner cross section, considering the effect of thermal radiation. In order to enhance the thermal conductivity of water which is considered as phase change material, TiO 2 − Cu Hybrid nanoparticles are added. Standard Galerkin Finite Element Method (FEM) along with adaptive mesh are employed to simulate the solidification process. Nanoparticles shape factor, radiation parameter and fractal pattern iteration are the key parameters which affect the solidification process in this study. Results depicted that increasing all these parameters results in decreasing the average temperature and total energy of the system, while the solid fraction experiences higher values, which causes the solidification process to be accelerated. Highlights • TiO2–Cu/water hybrid nanofluid solidification is investigated. • Koch snowflake fractal cross section is employed to enhance the thermal penetration depth. • Standard Galerkin FEM is applied to solve the unsteady governing equations. • Increasing thermal radiation parameter accelerates the solidification process. [ABSTRACT FROM AUTHOR]

Abstract This paper presents a comprehensive and accurate algorithm based on circuit model to design reflect-array antennas (RAAs). The proposed algorithm can extract geometry of RAA structure corresponding to radiation parameters without employing any approximation or optimization intervention into the algorithm. Simulation results for some comprehensive examples, verify the validity of the proposed algorithm. This method is simple, fast, accurate, and can be expanded to all species of RAAs with arbitrary geometries. One of the main problems confronted in RAAs is low bandwidth characteristics. To attain wide bandwidth, we exploited the proposed algorithm with combination of multi-layer design of RAAs and subwavelength element. Convergence is observed between simulation and fabrication results, asserting good accuracy in method. In 10–15 GHz band, the maximum gain and -1dB bandwidth of two-layer antenna is 31.4 dB and 18.5%, respectively. [ABSTRACT FROM AUTHOR]

In this paper, the Dufour and Soret effects on an unsteady MHD free convection flow of an incompressible, electrically conducting viscous Newtonian fluid past an infinite vertical porous plate have been studied, taking into account Viscous and Darcy resistance terms and constant permeability of the medium in the presence of radiation. The fluid is considered as a gray, absorbing-emitting but non-scattering medium. The Rosseland approximation in the energy equation is used to describe the radiative heat flux for optically thick fluid. The dimensionless governing equations for this investigation are solved numerically using Galerkin finite element method. The influence of the physical parameters involved in the problem under investigation on the velocity, temperature and concentration profiles within the boundary layer are presented through the graphs and tabulated results for the skin-friction coefficient, Nusselt and Sherwood numbers. [ABSTRACT FROM AUTHOR]

Effects of radiative heat transfer on MHD fully developed mixed convective flow of a viscous incompressible electrically conducting fluid through a vertical channel with asymmetric heating of the walls in the presence of a uniform transverse magnetic field has been studied. An exact solution of the governing equations has been obtained in closed form. It is observed that the velocity field is greatly influenced by the radiative heat transfer as well as bouyancy forces. The induced magnetic field decreases at any point near the left wall and it increases near the right wall of the vertical channel with increase in radiation parameter. Further, an increase in radiation parameter leads to a decrease in the temperature at any point of the channel flow. A limiting consideration of the solutions of the governing equations of the flow are analyzed for Ra<

Thermosolutal convection in a square cavity filled with a binary perfect gas mixture and submitted to an oriented magnetic field taking into account the effect of radiation heat transfer is numerically investigated. The cavity is heated and cooled along the active walls whereas the two other walls are adiabatic and insulated. Entropy generation due to heat and mass transfer, fluid friction and magnetic effect has been determined for laminar flow by solving numerically: The continuity, momentum energy and mass balance equations, using a Control Volume Finite-Element Method. The structure of the studied flows depends on five dimensionless parameters which are: The Grashof number, the buoyancy ratio, the Hartman number, the inclination angle of the magnetic field and the radiation parameter.

A theoretical analysis of free convective MHD flow of an unsteady rotating dusty fluid under the influence of hall current and radiation effect is carried out. The fluid flow is considered in the porous media under the influence of periodic pressure gradient and the fluid is assumed to be viscous, incompressible and electrically conducting with uniform distribution of dust particles. The governing partial differential equations are solved analytically using perturbation technique and the expressions for skin-friction is also derived. Further the effect of various pertinent parameter like magnetic parameter, rotation parameter and Hall current parameter on velocity of both fluid and dust phases are depicted graphically and the effect of radiation parameter, Grashof number and Prandtl number on temperature profile is also discussed in detail. [ABSTRACT FROM AUTHOR]

Non-Newtonian boundary layer flow and heat transfer characteristics over a stretching surface with thermal radiation and slip condition at the surface is analyzed. The flow is subject to a uniform transverse magnetic field. The suitable local similarity transformations are used to transform the non-linear partial differential equations into system of ordinary differential equations. The non-linear ordinary differential equations are linearized by using quasi-linearization technique. The implicit finite difference scheme has been adopted to solve the obtained coupled ordinary differential equations. The important finding in this communication is the combined effects of magnetic field parameter, power law index, slip parameter, radiation parameter, surface temperature parameter, heat source/sink parameter, local Eckert number, temperature difference parameter, generalized local Prandtl number on velocity and temperature profiles and also the skin-friction coefficient -f''(0), and heat transfer coefficient -f'(0) results are discussed. The results pertaining to the present study indicate that as the increase of magnetic field parameter, slip parameter decreases the velocity profiles, whereas the temperature profiles increases for both Newtonian and non-Newtonian fluids. The power law index and heat source/sink parameter decreases the dimensionless velocity and temperature profiles. The effect of radiation parameter, Eckert number leads to increase the dimensionless temperature. It is found that increasing the slip parameter has the effect of decreasing the skin-friction coefficient -f''(0) and heat transfer coefficient -f'(0). With the increase of power law index is to reduce the skin-friction coefficient and increase the heat transfer coefficient. [ABSTRACT FROM AUTHOR]

In this present article, we analyzed the nonlinear unsteady MHD flow of viscous, incompressible and electrically conducting fluid past a vertical porous channel under the influence of thermal radiation and chemical reaction. The transformed conservation equations are solved analytically subject to physically appropriate boundary conditions by using two term perturbation technique. The influence of a number of emerging non-dimensional parameters namely, Magnetic parameter, Prandtl number, Chemical reaction parameter, Thermal radiation parameter and Schmidt number examined in detail. Furthermore, the influence of these parameters on heat transfer rate and skin friction is also investigated. It is observed that the velocity is decreased with increasing chemical reaction parameter. Increasing rarefaction parameter increases the velocity and but increasing suction parameter decreases the velocity. The study is relevant to chemical materials processing applications. [ABSTRACT FROM AUTHOR]

This work provides a comprehensive theoretical analysis of MHD unsteady free convection viscoelastic fluid flow through a porous medium. The medium is treated as incompressible and optically transparent. The flow of the fluid is initiated by shearing action of the moving wall with time dependent suction. Radiative heat flow is considered in temperature equation. The coupled non-linear problem has been solved asymptotically. Approximate solutions have been obtained for the mean velocity, mean temperature using multi parameter perturbation technique. The originality of the present study is to investigate the effect of viscoelastic property of the fluid (Walters B ′ model) on the flow and heat transfer phenomena when the flow is permeated through a porous medium with uniform porous matrix subject to transverse magnetic field and time dependent fluctuative suction at the boundary surface. The case of viscous flow has been discussed as a particular case on comparison with the result reported earlier and it is in good agreement. Flow reversal is indicated incase of viscoelastic fluid with high heat capacity in the presence of magnetic field. The higher cooling of the plate in case of viscoelastic flow also causes a flow reversal. [ABSTRACT FROM AUTHOR]

The numerical investigation of Newtonian heating effect on unsteady MHD free convective flow of radiating and chemically reacting Casson hybrid nanofluid past an infinite oscillating vertical plate embedded in a porous medium is conducted by considering the effects of heat sink and viscous dissipation. The fluid motion is persuaded due to the periodic oscillations of the plate along its length. First order consistent chemical reaction and heat absorption are also regarded. The Silver and Titania nano-particles are disseminated in base fluid water and ethylene glycol combination to be formed hybrid nanofluid. This phenomenon is represented as non-linear partial differential equations with initial and boundary conditions. By introducing suitable non-dimensional variable and parameters, the governing equation with initial and boundary conditions are converted into dimensionless form, which are then solved numerically using a finite difference method. It is considered as the values of Hartmann parameter 0 < M ≤ 2; the values of the penetrability parameter are 0 < K ≤ 3; Casson fluid parameter 0 < α < 4; thermal Grashof number 0 < Gr ≤ 20, mass Grashof number 0 < Gm ≤ 12; heat source parameter 0 < Q ≤ 8; the values of ϕ 1 and ϕ 2 volume fractions of Ag and TiO 2 are 0.01, 0.05, 0.1 and 0.15; the Schmidt number as Sc = 0.22, 0.3, 0.6, 0.78 this analogous to hydrogen, helium, water vapours, as well as ammonia respectively; chemical reaction parameter 0 < Kc ≤ 4. The effects of several pertinent parameters on the velocity, temperature and concentration are displayed graphically whilst the effects of these parameters on the skin friction, Nusselt and Sherwood numbers are exhibited in tabular format and then discussed in detail. The velocity distribution is enhanced with increasing in permeability parameter, Newtonian heating parameter and thermal Grashof number whereas it is reduced with increasing Hartmann number, heat absorption parameter and Casson fluid parameter. Heat transport participates the significant role during the managing and dispensation of Casson fluids. This is of immense significance in numerous engineering applications, they are, transpiration cooling, termite welding, drag reduction as well as heat recovery of oils. In addition, this plays the enlargement of bio-convection prototypes produced by the populations of gravitactic microorganism in the porous media. [ABSTRACT FROM AUTHOR]

Effects of radiative heat transfer on an MHD fully developed mixed convective flow of a viscous incompressible electrically conducting fluid through a vertical channel with asymmetric heating of walls in the presence of a uniform transverse magnetic field has been studied. An exact solution of the governing equations has been obtained in closed form. It is observed that the velocity field is greatly influenced by the radiative heat transfer as well as bouyancy forces. The induced magnetic field decreases near the cool wall and it increases near the hot wall of the channel with an increase in radiation parameter. Further, an increase in radiation parameter leads to a decrease in the fluid temperature in the channel. A limiting consideration of the solutions of the governing equations of the flow are analyzed for Ra⪡1. [ABSTRACT FROM AUTHOR]

Thermosolutal convection in a square cavity filled with a binary perfect gas mixture and submitted to an oriented magnetic field taking into account the effect of radiation heat transfer is numerically investigated. The cavity is heated and cooled along the active walls whereas the two other walls are adiabatic and insulated. Entropy generation due to heat and mass transfer, fluid friction and magnetic effect has been determined for laminar flow by solving numerically: The continuity, momentum energy and mass balance equations, using a Control Volume Finite-Element Method. The structure of the studied flows depends on five dimensionless parameters which are: The Grashof number, the buoyancy ratio, the Hartman number, the inclination angle of the magnetic field and the radiation parameter. [ABSTRACT FROM AUTHOR]

In this article, the behaviors of radiation and thermal-diffusion on Walters' B model toward a vertical stretching surface with volumetric heat generation/absorption are examined. The system of nonlinear ordinary differential equations which are responsible for the behaviors of momentum, energy and concentration equations in relation to Velocity f ′ (η), temperature θ (η) and concentration ∅(η) are obtained by befitting similarity transformation and solved with Homotopy-Analysis-Method(HAM). The behaviors of various partients are discussed by virtue of graphs and tables as well as the convergence of the series solution and the iterations. It is noticed among others that the presence of Weissengerg number makes the problem to exhibit non-Newtonian property which steered-up viscoelasticity via the tensile stress and lower the momentum layer while various values of thermal-buoyancy contributes to the cooling of the sheet with adverse effect in Technological field for cooling of an electronic components and other materials. [ABSTRACT FROM AUTHOR]

In this article, two-dimensional boundary layer flow describing the impact of radiation and chemical reaction on stagnation-point flow of Hydromagnetic Walters' B fluid over a stretching surface is studied. The corresponding partial differential equations are converted to ordinary differential equations through the appropriate transformation variables and solved by Homotopy Analysis Method. The embedded parameters are discussed on dimensionless Velocity f ′ (η), Temperature θ (η) and Concentration ∅(η) profiles as well as tables for the Skin-friction, Nusselt number and Schwood number. The result reveals among other that the presence of Newtonian heating (γ > 0) magnifies temperature distribution and as a result, the quiescent fluid experiences thermal effect which play an important role in drying of the component while large values of radiation parameter pioneer radiative flux which magnifies the polymeric flow. [ABSTRACT FROM AUTHOR]