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This investigation deals with a comparison of suction/injection effect on flow, heat and mass transfer in porous media using a combined similarity-numerical solution. With this method of transformation, the governing transport PDEs are transformed into ODE and then solved numerically. The study reveals that suction/injection effect is more pronounce on the velocity distribution of a creeping flow (Darcy flow). The Darcy-Forchheimer flow has the steepest velocity curves due to non-linearity and has higher skin friction, heat and mass transfer rate when compared to the other porous media investigated.

The steady free convective boundary layer viscous fluid flow and heat transfer towards the moving flat plate is investigated. It is important to study the fluid flow and heat transfer problems in the presence of suction and injection effects due to an extensive variety of applications in engineering and industry. Thus, the main objective of the present study is to analyse the impacts of the suction and injection parameter on the velocity and temperature of the fluid as well as the skin friction and the Nusselt number coefficients. The problem has coupled partial differential equations which are converted into ordinary differential equations by employing similarity transformation and adopting of the strong wall suction. The ordinary differential equations thus obtain are handled numerically by utilizing Maple software simulation. The main findings concerning the behaviours of velocity and temperature against various values of the emerging physical parameter such as suction/injection are presented clearly in this numerical examination via graphical illustrations whose physical explanation are discussed thoroughly based on a strong theoretical basis. Furthermore, skin friction and Nusselt number results are studied at different values of pressure gradient. The detail geometry reveals that the velocity and temperature of the fluid decreases with increase of suction/injection parameter. Both skin friction coefficient and Nusselt number decreases with an increase of suction/injection parameter.

In this article, the mass and heat transfer flow of Ag–kerosene oil nanofluid over a cone under the effects of suction/injection, magnetic field, thermophoresis, Brownian diffusion, and Ohmic-viscous dissipation was examined. On applying the suitable transformation, PDEs directing the flow of nanofluid were molded to dimensionless ODEs. The solution of the reduced boundary value problem was accomplished by applying Runge–Kutta–Fehlberg method via shooting scheme and the upshots were sketched and interpreted. The values of shear stress and coefficients of heat and mass transfer were attained for some selected values of governing factors. The obtained results showed that when the amount of surface mass flux shifts from injection to the suction domain, the heat and mass transfer rate grew uniformly. However, they have regularly condensed with the rise in the magnitude of the magnetic field and particle volume fraction. Several researches have been done using cone-shaped geometry under the influence of various factors affecting the fluid flow, yet, there exists no such investigation that incorporated the response of viscous-Ohmic dissipation, heat absorption/generation, suction/blowing, Brownian diffusion, and thermophoresis on the hydro-magnetic flow of silver-kerosene oil nanofluid over a cone.

A theoretical study on the asymptotic suction/injection magnetohydrodynamic flow as a result of a uniform freestream couple stress fluid flowing over a flat surface is undertaken in the current study. It is targeted to obtain exact flow and temperature solutions representing the permeable couple stress fluid flow. Analytical expressions are extracted to derive interesting engineering tools such as momentum layer thickness, thermal layer thickness, wall shear stress, and heat transfer rate. The physical parameters leading to the existence of wall suction/injection solutions are determined with their thresholds. Momentum and thermal layer analysis from the present results clearly reveal how they are influenced by the presence of electrically conducting couple stress fluid. Further flow studies of similar kind will certainly benefit from the presented formulae.

The present work is concerned with an analytical study of entropy generation in viscous, incompressible fluid in an inclined channel with porous walls. The solution of the governing equations were obtained in closed form. The expression for the irreversibility ratio was also obtained and the results were presented graphically and extensively discussed for different values of the dimensionless parameters. The result indicates that wall inclination enhance entropy generation.

The present article studies the effects of suction/injection and variable physical properties on steady natural convection flow through a vertical channel. The investigation was done analytically using Differential Transformation Method (DTM). The variability in viscosity and thermal conductivity are considered linear function of temperature. The governing equations are transformed into a set of coupled nonlinear ordinary differential equations. Results obtained were compared with exact solution when some of the flow conditions were relaxed and results from DTM show an excellent agreement with the exact solution which was obtained analytically. The influence of the flow parameters on fluid temperature, concentration, and velocity are presented graphically and discussed for variations of the governing parameters. From the course of investigation, it was found that an increase in suction (S > 0) through the heated plate causes fluid temperature, velocity as well as concentration to decrease. However, an increase in injection causes heat transfer rate as well as skin friction at the heated plate to decrease.

The mathematical model responsible for fully developed laminar transient flow formation between the gaps of two stationary concentric porous tubes due to the imposition of azimuthal pressure gradient (Dean flow) is solved semi-analytically. The tubes walls are porous so that a radial flow can be superimposed. The solution of the momentum and continuity equations are obtained semi-analytically by using the combination of Laplace transform technique and a Laplace inversion method called Riemann sum approximation method. The solutions for skin friction at [Formula: see text] (outer surface of the inner porous tube) and [Formula: see text] (inner surface of the outer porous tube) are presented. The impact of suction/injection parameter and the ratio of the radii of the tubes are examined for the velocity profile and skin friction. Results show that the velocity profile decreases with increase in suction/injection parameter for various values of time, [Formula: see text] and at large value of time, ([Formula: see text]), the velocity and the skin friction attain a steady state.

Manufacturing of modern coating materials doped with magnetic nanoparticles has arisen as an exciting new area of materials processing fluid dynamics. Methanol is primarily used in chemical manufacturing, specialized vehicles fuel, energy carrier, as an antifreeze in pipelines, in wastewater treatment plant, and many more. In this article, a mathematical model is therefore developed to study crosswise flow of methanol-based ferromagnetic fluid through a permeable medium with suction/injection effects. Temperature-dependent viscosity is taken with Reynolds exponential model. The Tiwari–Das and Maxwell–Garnett nanofluid models are used, which alters the electrical conductivity, density, and thermal conductivity properties with nanoparticle volume fraction. The two-dimensional mass, momentum, and energy equations are normalized into nonlinear system comprising ordinary differential equations via appropriate similarity transformations. The solution of the emerging physical problem is attained by shooting scheme in MATLAB symbolic software. Validation of the results is presented through comparison with previously reported literature in the limiting sense. The influence of pertinent parameters on the flow and heat transfer characteristics is revealed through graphs. It is found that velocity profiles are suppressed with greater magnetic parameter and porosity parameters but temperature profile is enhanced. Velocity and temperature profiles for injection case are higher when compared with the suction phenomenon. Shear stress at the wall is decreased with volume fraction. Heat transfer gradient at the wall is significantly enhanced with volume fraction.

This article describes the effects of Joule heating and chemical reaction on unsteady MHD mixed convective micropolar fluid over a stretching sheet in presence of radiation, non-uniform heat source and porous medium. The arising non-linear coupled partial differential equations are reduced to a set of coupled non-linear ordinary differential equations and then solved numerically by using the Runge– Kutta–Fehlberg fourth–fifth order method along shooting technique. The graphical and tabular results elucidate the influence of different non-dimensional governing parameters on the velocity, temperature and concentration fields along with the wall friction, local Nusselt and Sherwood numbers. We found the dual nature of the solutions for suction and injection cases. A good agreement of the present results has been observed by comparing with the existing literature results.

The theoretical study of laminar boundary layer flows of a non-Newtonian fluid past a stretching sheet in an embedded porous medium in the presence of suction/injection is of significant importance in the crystal growing, geothermal, metallurgical, polymer extrusion and several other technological processes. Casson fluid model is one such fluid model used to characterize the behaviour of non-Newtonian fluids. The present article discusses the Casson fluid flow past a permeable stretching sheet in the presence of mass transpiration. The physical problem is modelled into a system of nonlinear partial differential equations which are analytically solved by transforming them into nonlinear ordinary differential equations with constant coefficient by means of similarity transformations. The analysis reveals the effect of Casson parameter on the velocity boundary. In fact, the increasing Casson parameter results in the suppression of velocity boundary. It is found that the skin friction coefficient decreases with the decreasing values of Casson parameter. The effects of Darcy drag force and the mass transpiration are also analyzed by means of various plots.

This research work is focused on the effects of combined heat and mass transfer on MHD stagnation point flow of Carreau nanaofluid embedded in porous medium with heat source. Thermal radiation and chemical reaction are also taken into account. The governing non-linear PDEs are transformed into a set of non-linear coupled ODEs which are then solved numerically by using the Runge– Kutta–Fehlberg fourth–fifth order method along shooting technique. The graphical and tabular results elucidate the influence of different non-dimensional governing parameters on the velocity, temperature and concentration fields along with the wall friction, local Nusselt and Sherwood numbers. We found the dual nature of the solutions for suction and injection cases. A good agreement of the present results has been observed by comparing with the existing literature results.

In this paper, the hydromagnetic stagnation point flow and temporal stability of Fe3O4-water ferrofluid over a convectively heated permeable stretching/shrinking sheet is theoretically investigated. The model equations of momentum and energy balance are obtained and transformed into ordinary differential equations using appropriate similarity variable. Using shooting method together with Runge-Kutta-Fehlberg numerical scheme the model nonlinear boundary value problem is tackled numerically. Pertinent results with respect to the basic steady flow velocity, temperature, skin friction and Nusselt number are obtained graphically and in tabular form. It is found that a critical value of shrinking parameter (λc) exists below which no real solution can be found. In addition, dual solutions (upper and lower branch) are observed for a range of shrinking/stretching parameter (λc

In this investigation, the heat and mass transfer characteristics in boundary layer flow about a stretching sheet in a porous medium filled with TiO2 – water and Al2O3 – water-based nanofluids, in ...

Effect of suction/injection on the rate of entropy generation of third grade fluid with convective cooling is analysed in this work. The highly non-linear boundary value problems obtained from the governing equations are solved by Adomian decomposition method (ADM). Some plots are presented to explain the influence of pertinent parameters on fluid motion, temperature, entropy generation and irreversibility ratio. From the results it is shown that suction/injection and third grade fluid parameters reduce fluid velocity across the channel, and increase in suction/injection parameter enhances fluid temperature while convective cooling parameter reduces it. Entropy generation is enhanced by suction/injection parameter at the lower wall but reduces it at the upper wall

An unsteady double diffusive mixed convection boundary layer flow over a vertically stretching sheet in the presence of suction/injection is investigated in this paper. The governing partial differential equations are reduced by applying suitable transformations to a set of nonlinear ordinary differential equations, which is solved by the Keller box method. The influence of various flow parameters on the velocity, temperature, and species concentration profiles of the fluid is studied. The effect of some problem parameters on the skin friction coefficient in the presence of suction/injection is considered.

This work studies the time-dependent convective flow of non-Newtonian power-law fluid by vertical plate. Fluid flow is studied in the presence of thermal radiation. The Buongiorno model is employed to describe the features of nanofluid. Entropy generation and Bejan number are calculated. The flow, temperature and concentration are given by the system of partial differential equations (PDE’s). The system of PDE’s is transformed into dimensionless form by transformation and then solve implementing finite difference technique. Special emphasis is given to the outcomes of Prandtl number, Reynolds number, Eckert number, radiation parameter, thermophoresis, Brownian parameter, and Schmidt number. Velocity, temperature, concentration, skin friction, Sherwood and Nusselt numbers are graphically analyzed. Graphical results show that velocity of fluid enhanced for high Grashof number while shows opposite behavior for Reynold number. For the high estimation of the thermophoresis parameter and Brownian motion parameter temperature and concentration increase. For the higher value of the radiation parameter, the irreversibility of fluid particles increases while the Bejan number decreases.

The effect of Suction – injection combination on the onset of Rayleigh – Bénard electroconvection micropolar fluid is investigated by making a linear stability analysis. The Rayleigh-Ritz technique is used to obtain the eigenvalues for different velocity and temperature boundary combinations. The influence of various parameters on the onset of convection has been analysed. It is found that the effect of Prandtl number on the stability of the system is dependent on the SIC being pro-gravity or anti-gravity. A similar Pe-sensitivity is found in respect of the critical wave number. It is observed that the fluid layer with suspended particles heated from below is more stable compared to the classical fluid layer without suspended particles.

Thermally driven steady mixed convective chemically reacting flow of an electrically conducting viscous incompressible fluid over a linearly stretching sheet in the presence of suction/injection, heat generation/absorption and thermal radiation is investigated. The governing nonlinear equations are transformed into ordinary differential equations using the similarity transformation, and linearized using the perturbation series expansions. The resulting linear similarity equations are solved semi-analytically using the Mathematica 9.0 software. Solutions of the concentration, temperature, velocity, Nusselt number, Sherwood number and skin friction are obtained, and presented graphically to illustrate the effects of the various parameters on the dependent flow variables. The results are extensively discussed. Furthermore, the results obtained are bench-marked with some of those obtained in the earlier studies in literature, and are found to be in consonance