Velocity and Thermal Slip Effects on Flow and Heat Transfer due to an Exponentially Stretching Sheet with Viscous Dissipation and

In this paper we have studied the flow and heat transfer characteristics of a viscous fluid in presence of viscous dissipation and thermal radiation due to an exponentially stretching sheet. The governing equations of this problem are basically highly non-linear partial differential equations which are converted into ordinary differential equations by using suitable similarity transformations techniques. These equations (pde’s) are converted into system of ordinary differential equations of first order and solved numerically by ode45 solver in MATLAB software. The effects of governing parameters on flow and heat transfer analyzed and interpreted through graphs. Numerical values of skin friction coefficients and Nusselt number are calculated for different values of governing parameters and tabulated. Under some limiting conditions our current result agree very well with available results in the literature

Thermal radiation effects on heat and mass transfer of magnetohydrodynamics Dusty Jeffrey fluid past an exponentially stretching sheet

The heat and mass transfer of steady magnetohydrodynamics of dusty Jeffrey fluid past an exponentially stretching sheet in the presence of thermal radiation have been investigated. The main purpose of this study is to conduct a detailed analysis of flow be- haviour of suspended dust particles in non-Newtonian fluid. The governing equations hav been converted into dimensionless form, and then solved numerically via the Keller-box method. The expression of Sherwood number, Nusselt number and skin friction have been evaluated, and then displayed in tabular forms. Velocity, temperature and concen- tration profiles are presented graphically. It is observed that large value of dust particles mass concentration parameter has reduced the flow velocity significantly. Increase in ra- diation parameter enhances the temperature, whereas the increment in Schmidt number parameter reduces the concentration

Bidirectionally Stretched Flow of Jeffrey Liquid with Nanoparticles, Rosseland Radiation and Variable Thermal Conductivity

Heat and mass transfer stretched flow of an incompressible, electrically conducting Jeffrey fluid has been studied numerically. Nanoparticles are suspended in the base fluid and it has many applications such as cooling of engines, thermal absorption systems, lubricants fuel cell, nanodrug delivery system and so on. Temperature dependent variable thermal conductivity with Rosseland approximation is taken into account and suction effect is employed in the boundary conditions. The governing partial differential equations are first transformed into set of ordinary differential equations using selected similarity transformations, which are then solved numerically using Runge-Kutta-Felhberg fourth-fifth order method along with shooting technique. The flow, heat and mass transfer characteristics with local Nusselt number for various physical parameters are presented graphically and a detailed discussion regarding the effect of flow parameters on velocity and temperature profiles are provided. It is found that, increase of variable thermal conductivity, radiation, Brownian motion and thermophoresis parameter increases the rate of heat transfer. Local Nusseltnumber has been computed for various parameters and it is observed that,in the presence of variable thermal conductivity and Rosseland approxima-tion, heat transfer characteristics are higher as compared to the constant thermal conductivity and linear thermal radiation

Influence of thermal radiation on unsteady MHD free convection flow of jeffrey fluid over a vertical plate with ramped wall temperature

Influence of thermal radiation on unsteady magnetohydrodynamic (MHD) free convection flow of Jeffrey fluid over a vertical plate with ramped wall temperature is studied. The Laplace transform technique is used to obtain the analytical solutions. Expressions for skin friction and Nusselt number are also obtained. Results of velocity and temperature distributions are shown graphically for embedded parameters such as Jeffrey fluid parameter , Prandtl number P r, Grashof number G r, Hartmann number H a, radiation parameter R d, and dimensionless time τ. It is observed that the amplitude of velocity and temperature profile for isothermal are always higher than ramped wall temperature

Radiation and Chemical Reaction Effects on MHD Thermosolutal Nanofluid Flow over a Vertical Plate in Porous Medium

In this study we discussed the influence of radiation and chemical reaction on MHD thermosolutal nanofluid convective slip flow over a vertical plate in porous medium in presence of thermophoresis and Brownian motion effects. The governing boundary layer partial differential equations are transformed into system of ordinary differential equations by using similarity transformation and then solved numerically using bvp5c Matlab package. The effects of dimensionless governing parameters on the flow, heat and mass transfer was discussed and presented through graphs. Also, the skin friction coefficient and local Nusselt and Sherwood numbers are computed and discussed. Results indicate that an increase in chemical reaction parameter enhances the mass transfer rate. Keywords: MHD, Radiation, Chemical Reaction, Nanofluid, Convection

Effects of ramped wall temperature and concentration on viscoelastic Jeffrey’s fluid flows from a vertical permeable cone

In thermo-fluid dynamics, free convection flows external to different geometries such as cylinders, ellipses, spheres, curved walls, wavy plates, cones etc. play major role in various industrial and process engineering systems. The thermal buoyancy force associated with natural convection flows can exert a critical role in determining skin friction and heat transfer rates at the boundary. In thermal engineering, natural convection flows from cones has gained exceptional interest. A theoretical analysis is developed to investigate the nonlinear, steady-state, laminar, non-isothermal convection boundary layer flows of viscoelastic fluid from a vertical permeable cone with a power-law variation in both temperature and concentration. The Jeffery’s viscoelastic model simulates the non-Newtonian characteristics of polymers, which constitutes the novelty of the present work. The transformed conservation equations for linear momentum, energy and concentration are solved numerically under physically viable boundary conditions using the finite-differences Keller-Box scheme. The impact of Deborah number (De), ratio of relaxation to retardation time (λ), surface suction/injection parameter (fw), power-law exponent (n), buoyancy ratio parameter (N) and dimensionless tangential coordinate (Ѯ) on velocity, surface temperature, concentration, local skin friction, heat transfer rate and mass transfer rate in the boundary layer regime are presented graphically. It is observed that increasing values of De reduces velocity whereas the temperature and concentration are increased slightly. Increasing λ enhance velocity however reduces temperature and concentration slightly. The heat and mass transfer rate are found to decrease with increasing De and increase with increasing values of λ. The skin friction is found to decrease with a rise in De whereas it is elevated with increasing values of λ. Increasing values of fw and n, decelerates the flow and also cools the boundary layer i.e. reduces temperature and also concentration. The study is relevant to chemical engineering systems, solvent and polymeric processes

The impact of variable fluid properties on hydromagnetic boundary layer and heat transfer flows over an exponentially stretching sheet

This paper put forward an analysis of variable fluid properties and their impact on hydromagnetic boundary and thermal layers in a quiescent fluid which is developed due to the exponentially stretching sheet. The viscous incompressible fluid has been set into motion due to aforementioned sheet. We assume that the viscosity and the thermal conductivity of the Newtonian fluid are temperature dependent. The governing boundary layer equations containing continuity, momentum and energy equations are coupled and nonlinear in nature, thereby, cannot be solvable easily by using analytical methods. Since the general boundary layer equations admits a similarity solutions, thus a generalized Howarth-Dorodnitsyn transformations have been exploited for the set-up of a coupled nonlinear ODEs. These transformed ODEs are solved numerically by a shooting method and is verified from MATLAB built-in collocation solver bvp4c for different parameters appearing in the work. We show results graphically and in a tabulated form for a constant and a variable fluid properties. We find that the temperature dependent variable viscosity and a thermal conductivity influence a velocity and a temperature profiles. We show that the thermal boundary layer decreases for constant variable fluid properties and increases for variable fluid propertiesThe impact of variable fluid properties on hydromagnetic boundary layer and heat transfer flows over an exponentially stretching sheetpublishedVersio

Unequal diffusivities case of homogeneous–heterogeneous reactions within viscoelastic fluid flow in the presence of induced magnetic-field and nonlinear thermal radiation

AbstractThis article presents the effects of nonlinear thermal radiation and induced magnetic field on viscoelastic fluid flow toward a stagnation point. It is assumed that there exists a kind of chemical reaction between chemical species A and B. The diffusion coefficients of the two chemical species in the viscoelastic fluid flow are unequal. Since chemical species B is a catalyst at the horizontal surface, hence homogeneous and heterogeneous schemes are of the isothermal cubic autocatalytic reaction and first order reaction respectively. The transformed governing equations are solved numerically using Runge–Kutta integration scheme along with Newton’s method. Good agreement is obtained between present and published numerical results for a limiting case. The influence of some pertinent parameters on skin friction coefficient, local heat transfer rate, together with velocity, induced magnetic field, temperature, and concentration profiles is illustrated graphically and discussed. Based on all of these assumptions, results indicate that the effects of induced magnetic and viscoelastic parameters on velocity, transverse velocity and velocity of induced magnetic field are almost the same but opposite in nature. The strength of heterogeneous reaction parameter is very helpful to reduce the concentration of bulk fluid and increase the concentration of catalyst at the surface

MHD Free Convection Boundary Layer Flow of a Nanofluid over a Permeable Shrinking Sheet in the Presence of Thermal Radiation and Chemical Reaction

The objective of this work is to analyze the chemical reaction and thermal radiation effects on MHD free convection boundary layer low of a nanofluid over a permeable shrinking sheet. The model used for the nanofluid incorporates with Brownian and thermophoresis effects. A mathematical formulation has designed for momentum, temperature and nanofluid solid volume profiles. The highly nonlinear coupled partial differential equations are simplified with the help of suitable similarity transformations. The reduced partial differential equations are solved using the Method of line. The entire computation procedure is implemented using a program written and carried out using Mathematica computer language. The results for the dimensionless velocity, temperature, and nanofluid solid volume profiles are discussed with the help of graphs and tables. We have examined the effects of various controlling flow parameters namely unsteadiness parameter A, magnetic parameter M, thermal radiation parameter R, Prandtl number Pr, Brownian motion parameter Nb, thermophoresis parameter Nt, Radiation parameter Nr and Lewis number Le on the dimensionless velocity, temperature and nanoparticle volume fraction profiles.. Keywords: Nanofluid, Magentohydrodynamics (MHD), permeable shrinking sheet, chemical reaction, heat source, Thermal Radiation

Thermophoresis and Brownian motion effects on chemically reacting Casson fluid flow past a nonlinear stretching sheet

In this study, we analyzed the effects of heat source/sink on boundary layer flow of a MHD Casson fluid past a nonlinear stretching sheet with thermophoresis and Brownian motion. The governing partial differential equations are transformed in to set of ordinary differential equations by using similarity transformation and solved numerically using bvp5c Matlab package. The effects of chemical reaction parameter, magnetic field parameter, heat source/sink, Brownian motion parameter and thermophoresis parameter on velocity, temperature and concentration profiles are discussed and presented through graphs. Results indicate that an increase in heat source/sink parameter enhances the heat transfer rate. Keywords: Casson fluid, Radiation, MHD, Heat source/sink, Thermophoresis and Brownian motion