Convective Mass Transfer Flow Research Articles

MHD free convective heat and mass transfer flow passing through semi‐infinite plate for Cu‐water and TiO2‐water nanofluids in presence of radiation embedded in porous medium

AbstractThis research presents an analytical study of magnetohydrodynamics (MHD)‐free convective heat and mass transfer flow of a nanofluid bounded by a semi‐infinite flat plate. A magnetic field of strength is applied throughout the fluid region. The plate is moving with a constant velocity , temperature, and the concentration are assumed to be fluctuating with time harmonically from a constant mean at the plate. The frontier equations are assumed to be of an oscillatory nature and cracked analytically using the perturbation technique. The novelty of the present work is to examine the heat and mass transfer MHD flow for Cu‐water and TiO2‐water nanofluids in the presence of thermal radiation. The influence of physical parameters on the flow domain is described in the discussions by graphically and in tabular form. It was found that the fluid temperature and skin friction were reduced with the increased values of the radiation parameters for Cu‐water and TiO2‐water nanofluids. Also, it is noticed that the concentration boundary layer thickness decreases with an increase in chemical reaction parameters.

Impact of variable electrical conductivity, viscosity on convective heat and mass transfer flow of CuO- and Al2O3-water nanofluids in cylindrical annulus

In the food industry, electrical conductivity is essential for heating processes. The dependence on temperature conductivity of electricity on the outermost layers flow of the nanofluid is the main topic of this paper. Variable electrical conductivity, viscosity, thermo diffusion, thermal radiation and radiation absorption on convective heat and mass transfer flow Cuo and Al2O3-water nano-fluids confined in cylindrical annulus. The non-linear governing equations have been solved by finite element technique with quadratic approximation functions. For various parametric adjustments, the temperature, speed, and nanoconcentration have all been examined. Similar to the cylindrical wall, quantitative evaluations have been made of the surface resistance, temperature rate and mass transport. It is discovered that for both types of nanofluids, a higher thermo-diffusion effect leads to a lower concentration and Sherwood digits on the cylinders. An augment in Q1 enriches the rapidity in CuO-water nanofluidic system as well as decreases in Al2O3-water nanofluidic. Increased Q1 lowers the real temperature and nanoconcentration in both types of nanofluids.

MHD nonlinear natural convection from a uniformly moving porous vertical plate with constant heat and mass flux in the presence of thermal radiation, diffusion‐thermo, heat sink, and chemical reaction

AbstractAn attempt has been made to investigate the problem of nonlinear free convection heat and mass transfer flow past an infinite vertical porous plate embedded in a porous medium by taking into account thermal radiation and heat sink with constant heat and mass flux. Transversely oriented and of uniform strength , a magnetic field has been introduced to the fluid area. The nonlinear density variation with temperature as well as concentration are the basis for the current physical situation, which is explained by this mathematical model. Exact solutions are derived for momentum equation, energy equation, and species continuity equation under the relevant boundary conditions. The dimensionless governing equations are analytically solved. The influence of various physical parameters, such as Dufour number, Schmidt number, thermal Grashof number, magnetic parameter, mass Grashof number, heat sink, thermal radiation, Prandtl number, chemical reaction parameter on the flow, and transport characteristic, has been presented graphically and in tabular form. The novelty of the present investigation is that here both constant heat and mass flux at the plate are taken into account in addition to thermal radiation and heat sink. The findings of the mathematical study demonstrate that velocity, temperature, and skin friction intensify with a rise in the Dufour number this is due to the fact that the convection current becomes stronger as the Dufour number rises. Fluid's concentration declines as the Schmidt number grows, or the concentration rises as the mass diffusivity rises. Fluid temperature is enhanced with high thermal diffusivity. Frictional resistance on the plate hikes due to thermal buoyancy force.

Influence of inclined magnetic field and cross diffusion on transient forced convective heat and mass transfer flow along a porous wedge with variable Prandtl number

The unsteady 2-D forced convective mass and heat transfer flow of an incompressible, viscous and electrically conducting fluid along a porous wedge is examined in this article using numerical analysis to survey the effects of a magnetic field and thermophoresis. This is done in the existence of temperature-dependent thermal conductivity, a variable Prandtl number, and the effect of cross diffusion. The governing nonlinear PDEs have been converted into nonlinear ODEs by using a similarity transformation. The modified ODEs are solved for similar solutions using the shooting technique and the Runge–Kutta fourth-order method. The temperature, velocity, concentration, thermophoretic velocity, and thermophoretic particle deposition velocity results for various parameters are provided. The Dufour number’s effect enhances the temperature profile and rate of heat transfer. Moreover, it is noted that the rate of mass transfer is meaningfully influenced by the variation of the thermophoresis parameter and Soret number. Thus, in any physical model where the thermal conductivity of the fluid is temperature dependent, the Prandtl number within the BL have to be treated as variable rather than constant.

Effect of thermal radiation on nonDarcy hydromagnetic convective heat and mass transfer flow of a water–SWCNT’s and MWCNT’s nanofluids in a cylindrical annulus with thermo-diffusion and chemical reaction

The examined through analysis of the movement of water-based single wall carbon nanotube (SWCNT) and multiwall carbon nanotube (MWCNT) nanofluids in a coordinate annulated zone under influence of non-uniform heat source/sink. By imposing the appropriate nondimensional variables, the governing partial differential equations are converted into a system of coupled nondimensional partial differential equations. By means of the usage of quadratic polynomials and the Galerkin finite element detail approach, the nonlinear equations have been executed. The expressions representing fluid velocity, temperature and concentration are discussed graphically. While skin friction, heat transfer and mass transfer are revealed in tabular structure. The proposed scheme is shown to have faster convergence than the existing scheme with excellent accuracy. Various parametric values have been analyzed and observed that higher temperatures and concentrations are produced with lower velocities with and bigger velocities with higher radiative heat flux or nanoparticle volume fraction.

Effect of Hall Currents on Transient Convective Heat and Mass Transfer Flow of a Viscous Fluid in a Vertical Wavy Channel with Tranveling Thermal Waves

Effect of Hall Currents on Transient Convective Heat and Mass Transfer Flow of a Viscous Fluid in a Vertical Wavy Channel with Tranveling Thermal Waves

Impact of porosity and radiation on two‐dimensional unsteady magnetohydrodynamics heat transfer stagnation point flow with viscous dissipation

AbstractThe current study aims to investigate the influence of porosity in the presence of radiation, and viscous dissipation on two‐dimensional unsteady magnetohydrodynamics mixed convection heat and mass transfer flow at the stagnation point. The governing time‐dependent nonlinear partial differential equations are converted into a nonlinear ordinary differential equation by utilizing similarity transformations. The transformed equations are solved by employing the bvp4c technique, a well‐known numerical approach. The influence of nondimensional factors on fluid velocity, temperature, and species concentration profiles is explored and graphically represented. For varied values of the Prandtl number, magnetic field, and Schmidt number, the friction factor, Nusselt, and Sherwood numbers are also explored and provided in tabular format. As increasing the porosity parameter, the temperature profile, concentration profile is growing, and velocity profile diminishes. The conclusions of this study are widely accepted by the scientific community.

Diffusion Thermo and Chemical Reaction Effects on Magnetohydrodynamic Jeffrey Nanofluid Over an Inclined Vertical Plate in the Presence of Radiation Absorption and Constant Heat Source

This article investigates the Diffusion thermo and chemical reaction effects on the free convection heat and mass transfer flow of Jeffrey nanofluids (Cu and TiO2) over an inclined porous vertical plate embedded in a porous medium in the presence of radiation absorption and constant heat source under fluctuating boundary conditions. The plate is moved with a constant velocity U0, temperature and the concentration are assumed to be fluctuating with time harmonically from a constant mean at the plate. Perturbation technique is applied to solve the governing equations of the flow and pointed out the variations in velocity, temperature and concentration with the use of graphical presentations. The impact of several parameters on local skin friction, Nusselt number and Sherwood number is also noticed and discussed. It is concluded that the resultant velocity reduces with increasing Jeffrey parameter and Suction parameter, velocity and Temperature enhances with increasing Radiation absorption parameter. Also it is noticed that the solutal boundary layer thickness decreases with an increase in chemical reaction parameter. It is because chemical molecular diffusivity reduces for higher values of Kr.

MHD natural convection heat and mass transfer flow over an inclined porous plate with thermophoresis and nonlinear thermal radiation effects

AbstractThis study examined magnetohydrodynamic natural convection mass and heat transfer flow of an electrically conducting and viscous incompressible fluid over an inclined porous plate with thermophoresis, suction/injection, and uniform magnetic field. The mathematical model governing the fluid behavior surrounding an inclined plate is solved through the Runge–Kutta–Fehlberg fourth–fifth order after utilizing the shooting method. The implication of active dimensionless parameters in the governing equations is fully discussed in detail. The results obtained show that, in the existence of nonlinear thermal radiation and suction/injection, the heat transfer rises with the increase in the angle of inclination but it decreases with the mass transfer and plate shear stress. Furthermore, the heat transfer rate experiences a serious setback due to the increase in the buoyancy force but improves the plate shear stress. The mass transfer is directly proportional to the thermophoresis effect. In addition, Particle suction increases the velocity and temperature curves while it declines the concentration profile, but the opposite is valid for injection. Nonlinear thermal radiation positively affects the temperature, velocity, and concentration profiles. The Lorentz force suppresses the fluid transport and retard the rate of particle concentration, but promotes the fluid temperature distribution. It is also deduced that increasing the rate of particle suction from 0 to 1, accounts for over 76% increase in the particle deposition at the plate surface. However, increasing the rate of particle injection from 0.004 to 0.250 accounts for an over 83% decrease in the particle deposition at the plate surface.

Nonlinear approximation for buoyancy-driven mixed convection heat and mass transfer flow over an inclined porous plate with Joule heating, nonlinear thermal radiation, viscous dissipation and thermophoresis effects

This study considered a classical magnetohydrodynamics (MHD) mixed convection heat and mass transfer flow over an inclined porous plate with thermophoresis, Joule heating, viscous dissipation, and nonlinear thermal radiation. The impact of nonlinear density variation with temperature and concentration (NDTC) in the buoyancy term is also taken into consideration. The mathematical model is first transformed into ordinary differential equations (ODEs) by similarity variables. The reduced ODEs are solved through the classical Runge–Kutta algorithm after utilizing the shooting technique. Some major findings of the analysis include; the heat transfer rate increases with the fluid injection but it decreases the rate of particle deposition and skin friction. Regarding the fluid suction, the heat transfer rate is observed to decrease as the fluid suction intensifies whereas increases the particle deposition and shear stress at the plate surface. As (a classical horizontal flat plate), the rate of heat transfer enhances but decreases the particle deposition rate and plate shear stress. With blowing/suction and in the presence of the magnetic parameter, the plate shear stress and heat transfer increase with nonlinear thermal radiation propagation whereas decreases the particle deposition. The species concentration near the porous plate, velocity, and temperature curves is enhanced by escalating the dissipation parameter. The radiative heat flux boosts the fluid temperature that consequently enhanced the velocity and the species concentration near the porous plate. The fluid velocity past the porous plate is higher in the case of a vertical plate () compared to the classical flow over a horizontal porous plate ().

Hall Current and Soret Effects on Unsteady MHD Rotating Flow of Second-Grade Fluid through Porous Media under the Influences of Thermal Radiation and Chemical Reactions

The unsteady MHD free convection heat and mass transfer flow of a viscous, incompressible, and electrically conducting fluid passing through a vertical plate embedded in a porous medium in the presence of chemical reactions and thermal radiation is investigated. The effects of the Hall current, rotation and Soret are studied. Using the perturbation approach, one can obtain an accurate analytical solution to the governing equations for the fluid velocity, fluid temperature, and species concentration, provided that the initial and boundary conditions are acceptable. It is possible to obtain expressions for the shear stress, rate of heat transfer, and rate of mass transfer for both plates with the ramping temperature and isothermal conditions. On the one hand, the numerical values of the primary and secondary fluid velocities, fluid temperature, and species concentration are presented graphically. On the other hand, the numerical values of the shear stress and rate of mass transfer for the plate are presented in tabular form for various values of the relevant flow parameters. These values are given for a range of pertinent flow parameters. It was determined that an increase in the Hall and Soret parameters over the whole fluid area leads to a corresponding increase in the resulting velocity. The resultant velocity continually climbs to a high level due to the contributions of the thermal and solute buoyancy forces. Lowering the heat source parameter reduces the temperature distribution, resulting in a lower overall temperature. When there is a rise in the chemical reaction parameter over the whole fluid area, there is a corresponding decrease in the concentration. The concentration buoyancy force, Hall current, and Prandtl number reduce the skin friction. On the other hand, the permeability of the porous medium, rotation, chemical reaction, the Soret number, thermal buoyancy force, and mass diffusion all have the opposite effects on the skin friction.

MHD Free Convective Heat and Mass Transfer Flow from a Vertical Porous Surface with Variable Thermal Conductivity, Variable Mass Diffusivity and Thermal Diffusion Including Viscous Dissipation and Chemical Reaction

An analysis is carried out to study chemically reactive, viscous dissipative effects of an incompressible and electrically conducting fluid with MHD free convection adjacent to a vertical surface with variable thermal conductivity (VTD) and variable mass diffusivity (VMD). An approximate numerical solution for the steady laminar boundary layer flow over a wall of the surface in the presence of species concentration and thermal mass diffusion has been studied. Using numerical techniques the governing boundary layer equations are solved to get the exact solution. Numerical calculations are carried out for different values of dimensionless parameters. The results are exhibited through various graphs and it is observed from the analysis of the results that the velocity field is appreciably influenced by the magnetic effect, porous effect, chemical reaction and buoyancy ratio between the species and thermal diffusion at the wall of the surface.

Hall, Soret, and rotational effects on unsteady MHD rotating flow of a second-grade fluid through a porous medium in the presence of chemical reaction and aligned magnetic field

The effects of Hall current, rotation and Soret effects on an unsteady MHD free convection heat and mass transfer flow of a viscous, incompressible and electrically conducting fluid past an inclined plate embedded in a porous medium in the presence of chemical reaction and an aligned magnetic field are investigated. An exact analytical solution of the governing equations for fluid velocity, fluid temperature, and species concentration subject to appropriate initial and boundary conditions is obtained using the perturbation technique. Expressions for shear stress, rate of heat transfer and rate of mass transfer at the plate are derived for both ramped temperature and isothermal plates. The numerical values of primary and secondary fluid velocities, fluid temperature and species concentration are displayed graphically, whereas those of shear stress and rate of mass transfer at the plate are presented in tabular form for various values of pertinent flow parameters. It is concluded that, the resultant velocity is increased with an increasing in Hall and Soret parameters throughout fluid region. The thermal and solutal buoyancy forces contribute to the resultant velocity ever-increasing to high. The temperature distribution is trim downs through an increasing in heat source parameter. The concentration is reduced with an increase in the chemical reaction parameter in the entire fluid region. Concentration buoyancy force, hall current, and Prandtl number have tendency to reduce in skin friction whereas permeability of the porous medium, Rotation, chemical reaction, Soret number, thermal buoyancy force and mass diffusion have reverse effect on it.

Casson nanofluid performance on MHD convective flow past a semi‐infinite inclined permeable moving plate in presence of heat and mass transfer

AbstractThis article investigates the radiation and chemical reaction effects on the free convection heat and mass transfer flow of Casson nanofluids (Cu and TiO2) over an inclined porous vertical plate embedded in a porous medium in the presence of radiation absorption and constant heat source under fluctuating boundary conditions. The plate is moved with a constant velocity of U0, and temperature and the concentration are assumed to be fluctuating with time harmonically from a constant mean at the plate. The perturbation technique is applied to solve the governing equations of the flow and pointed out the variations in velocity, temperature, and concentration with the use of graphical presentations. The impact of several parameters on local skin friction, Nusselt number, and Sherwood number is also noticed and discussed. It is concluded that the resultant velocity reduces with increasing Casson parameter and suction parameter, velocity, and temperature enhanced with increasing radiation absorption and diffusion thermo parameters. Also, it is noticed that the solutal boundary layer thickness decreases with an increase in chemical reaction parameters. It is because chemical molecular diffusivity reduces for higher values of Kr.

Combined Influence of Thermal Radiation, ThermoDiffusion, Radiation Absorption on Mixed Convective Heat and Mass Transfer Flow of a Micropolar Fluid in a Vertical Channel with Variable Temperature in the presence of Heat Sources

The purpose of the present chapter is to analyze the thermal radiation, radiation absorption and thermo-diffusion on mixed convective heat and mass transfer flow of a micropolar fluid between two vertical parallel plates with varying temperature in the presence of heat sources. Such type of study may be applicable in nuclear reactors, heat exchangers and various electronic devices. The non-linear governinmg equations have been solved by employing Galerkin finite element technique with three nodded line segments.The velocity ,micro-rotation temperature and concentration have been analysed for different variations of Rd,Sr,Q1 , and p

Impact of Variable Viscosity, Activation Energy on MHD Mixed convective Heat and Mass Transfer Flow of a Nanofluid in a Cylindrical Annulus

We explore the impact of variable viscosity, activation energy on MHD mixed convective heat and mass transfer flow of nanofluid through a porous medium in a Co-axial cylindrical duct. The non-linear, coupled equations have been solved by using Galerkine finite method with quadratic polynomials. The behaviour of velocity, temperature and nanoconcentration is analyzed at different axial positions. The rate of heat and mass transfer has also been obtained for variations in the governing parameters. From the analysis we find that an increase in Nb and Nt reduces the velocity, increases the temperature and nanoconcentration.

Hall and Rotation Effects on Radiating and Reacting MHD Flow past an Accelerated Permeable Plate with Soret and Dufour Effects

This article investigates numerically the effects of Hall current and rotation effects on radiating and chemically reacting unsteady MHD natural convection flow past an accelerated infinite vertical permeable plate in the presence of Soret and Dufour effects. The dimensionless coupled non-linear governing partial differential equations of the problem are solved numerically by employing finite element method. The influence of various physical parameters influencing the flow on the primary velocity, secondary velocity, temperature and the species concentration are displayed graphically whilst the numerical results of the primary skin friction, secondary skin-friction, Nusselt number and the Sherwood number are presented in tabular form. Results reveals that magnetic parameter, radiation parameter and chemical reaction rate tends to depreciate both primary and secondary velocity components whilst Hall, Soret and Dufour effects have reverse trend. Rotation parameter tends to retard fluid flow in the primary flow direction and accelerate fluid flow in the secondary flow direction. Thermal boundary layer thickness decreases with increasing radiation parameter whilst the reverse trend is noticed with increasing Dufour effect. Thermal diffusion effect causes to improve concentration boundary layer thickness whilst chemical reaction rate has reverse impact. These parameters have similar effect on the primary and secondary skin-frictions whilst opposite effect was noticed on the Nusselt and Sherwood numbers. This model problem finds an important in engineering and industrial application such as MHD generators, food processing, heat exchangers devices and internal rotation rate of the sun.
 HIGHLIGHTS
 
 The problem investigate the effects of Hall current and rotation effects on radiating and reacting on unsteady magnetohydrodynamics (MHD) natural convection heat and mass transfer flow over an infinite vertical porous plate embedded in a uniform porous medium taking Soret and Dufour effects into account
 The resulting partial differential equations governing the fluid flow are solved numerically using the finite element method. In order to determine the effects of various pertinent parameters and to investigate the important flow features, the numerical calculations for fluid velocity, temperature and species concentration are computed and shown graphically whereas skin friction, Nusselt number and Sherwood number at the plate are evaluated and depicted in tabular form
 The model problem finds an important in engineering and industrial application
 
 GRAPHICAL ABSTRACT

Generalized Mittag-Leffler Kernel Form Solutions of Free Convection Heat and Mass Transfer Flow of Maxwell Fluid with Newtonian Heating: Prabhakar Fractional Derivative Approach

In this article, the effects of Newtonian heating along with wall slip condition on temperature is critically examined on unsteady magnetohydrodynamic (MHD) flows of Prabhakar-like non integer Maxwell fluid near an infinitely vertical plate under constant concentration. For the sake of generalized memory effects, a new mathematical fractional model is formulated based on a newly introduced Prabhakar fractional operator with generalized Fourier’s law and Fick’s law. This fractional model has been solved analytically and exact solutions for dimensionless velocity, concentration, and energy equations are calculated in terms of Mittag-Leffler functions by employing the Laplace transformation method. Physical impacts of different parameters such as α, Pr, β, Sc, Gr, γ, and Gm are studied and demonstrated graphically by Mathcad software. Furthermore, to validate our current results, some limiting models such as classical Maxwell model, classical Newtonian model, and fractional Newtonian model are recovered from Prabhakar fractional Maxwell fluid. Moreover, we compare the results between Maxwell and Newtonian fluids for both fractional and classical cases with and without slip conditions, showing that the movement of the Maxwell fluid is faster than viscous fluid. Additionally, it is visualized that both classical Maxwell and viscous fluid have relatively higher velocity as compared to fractional Maxwell and viscous fluid.

The memory time effects for unsteady seas and oceans water flow through the limestone porous medium in the presence of chemical reaction and Soret effects

AbstractIn this work, we study the effects of the thermal and diffusion memories in the seas and oceans water using the methodology of fractional calculus for modeling a viscous fluid. In our model, we derive a model with two fractional parameters representing the thermal and diffusion effects for this type of fluid. We formulate a problem of mixed convection heat and mass transfer flow of a viscous fluid through a Limestone porous medium in a vertical channel whose walls are kept at variable temperature and concentration. The influences of heat‐mass memories in the presence of chemical reaction, heat generation/absorption and, the Soret effect are discussed and represented graphically on all variables fields. Also, the influences of Darcy, Prandtl, Schmidt, Grashof parameters are compared with the effect of fractional parameters.

Numerical Investigation of Radiation Effects on MHD Convective Heat and Mass Transfer Flow Past a Semi-Infinite Vertical Moving Porous Plate in the Presence of Chemical Reaction

Abstract: The numerical solutions for heat and mass transfer by laminar flow of a Newtonian, viscous, electrically conducting and heat generation/absorbing fluid on a continuously vertical permeable surface in the presence of a radiation, a first-order homogeneous chemical reaction and the mass flux are considered. The plate is assumed to move with a constant velocity in the direction of fluid flow. A uniform magnetic field acts perpendicular to the porous surface, which absorbs the fluid with a suction velocity varying with time. The Equations of continuity, linear momentum, energy and diffusion, which govern the flow field, are solved by using a Finite Element Method. The results of the velocity, temperature, concentration, skin- friction, Nusselt number and Sherwood number has been discussed for variations in the governing parameters. Keywords: MHD, Radiation, Heat and Mass Transfer, Porous Medium, Unsteady flow, Finite Element Method.