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

Radiation, inclined magnetic field and cross-diffusion effects on flow over a stretching surface

AbstractThe steady two-dimensional flow over a vertical stretching surface in presence of aligned magnetic field, cross-diffusion and radiation effects are considered. The governing partial differential equations are transformed to nonlinear ordinary differential equation by using similarity transformation and then solved numerically by using bvp4c with MATLAB package. The effects of various non-dimensional governing parameters on velocity, temperature, concentration profiles along friction factor, Nusselt and Sherwood numbers are discussed and presented through graphs and tables’.We observed that increase in aligned angle strengthen the magnetic field and decreases the velocity profile of the flow and enhances the heat transfer rate. Comparisons with existed results are presented

Nonlinear radiative magnetohydrodynamic Falkner-Skan flow of Casson fluid over a w

This communication addresses the thermophoresis and Brownian motion effects on magnetohydrodynamic radiative Falkner-Skan flow of Casson fluid over a wedge with convective condition. In most of the existing studies thermal radiation is linear. Due to the noticeable significance of the numerous industrial as well as engineering applications, in this study we measured the thermal radiation is nonlinear. Numerical results are presented graphically as well as in tabular form with aid of Runge-Kutta and Newton’s methods. Effects of pertinent parameters on velocity, temperature and concentration distributions are presented and discussed for three wedge positions (i.e. static wedge, forward and backward movements of wedge). For engineering interest we also computed friction factor, heat and mass transfer rates. It is observed that thermal, concentration and momentum boundary layers are not uniform at different wedge positions. It is also observed that the heat and mass transfer rate is high when the wedge is moving in forward direction

Unsteady three-dimensional flow of Casson–Carreau fluids past a stretching surface

In this study, we investigated the effects of nonlinear thermal radiation and non-uniform heat source/sink in unsteady three-dimensional flow of Carreau and Casson fluids past a stretching surface in the presence of homogeneous–heterogeneous reactions. The transformed governing equations are solved numerically using Runge–Kutta based shooting technique. We obtained good accuracy of the present results by comparing with the already published literature. The influence of dimensionless governing parameters on velocity, temperature and concentration profiles along with the friction factors, local Nusselt and Sherwood numbers is discussed and presented graphically. We presented dual solutions for flow, heat and mass transfer in Carreau and Casson fluids. It is found that the heat and mass transfer rate in Casson fluid is significantly high while compared with the Carreau fluid

Effects of induced magnetic field and homogeneous–heterogeneous reactions on stagnation flow of a Casson fluid

In this study, we analyzed the induced magnetic field effect on the stagnation-point flow of a non-Newtonian fluid over a stretching sheet with homogeneous–heterogeneous reactions and non-uniform heat source or sink. The transformed ordinary differential equations are solved numerically using Runge–Kutta and Newton's method. For physical relevance we analyzed the behavior of homogeneous and heterogeneous profiles individually in the presence of induced magnetic field. The effects of different non-dimensional governing parameters on velocity, induced magnetic field, temperature and concentration profiles, along with the skin friction coefficient and local Nusselt number, are discussed and presented through graphs. The results of the present study are validated by comparing with the existed literature. Results indicate that induced magnetic field parameter and stretching ratio parameter have the tendency to enhance the heat transfer rate

Convective conditions and dissipation on Tangent Hyperbolic fluid over a chemically heating exponentially porous sheet

In this present analysis we investigated the steady-state magnetohydrodynamic boundary layer flow of tangent hyperbolic fluid over an exponentially stretching surface in the presence of heat source and chemical reaction. The chemical reaction with combination of exponential surface has significance in many industrial and manufacturing systems. The partial nonlinear differential equations are transformed into ordinary differential equations by using the similarity conversion and the accomplished boundary layer ordinary differential equations are elucidated numerically by using Shooting technique. The effects of numerous non-dimensional governing factors on velocity, temperature and concentration profiles were depicted graphically and analyzed in detail. The numerically computed results of Skin friction factor, Nusselt and Sherwood numbers are presented in tabular form for suction and injection cases separately.Heat transfer rate at the surface increases with increasing values of power law of index and whereas it declines with the magnetic field, heat source and chemical reaction parameters. It observed that Biot number enhances the skin friction, Nusselt number and decrease the Sherwood number.Heat transfer rate and mass transfer rate increases and skin friction decreases with increasing Eckert number

Viscous and Joule's dissipation on Casson fluid over a chemically reacting stretching sheet with inclined magnetic field and multiple slips

Multiple slips are most significant in many biological processes such as blood pumping from heart to various parts of body, endoscopy treatment, distribution of food and controlling the heat transport phenomena. By considering this, in the present investigation we analysed the multiple slips and joule's dissipation on magnetic Casson fluid over a stretching surface. To control the heat and mass transport phenomena we also included the heat source or sink, chemical reaction and thermal radiation. The arising physical governing systems of partial differential equations (PDEs) are transformed into ordinary differential equations (ODEs). The transformed governing equations are solved numerically by using Runge-Kutta-Fehlberg method. We presented the numerical solutions for various governing parameters (Eckert number, Joule heating parameter, velocity, thermal and mass slip parameters etc) on velocity, temperature and concentration profiles. Graphical and numerical results are described for the various parameters of attention entering into the modelled problems. The present numerical results are compared with published results. It is found that the slip have propensity to control the boundary layer flow

Cattaneo-Christov heat flux on UCM nanofluid flow across a melting surface with double stratification and exponential space dependent internal heat source

Melting and exponential space dependent internal heat source effects on magnetohydrodynamic of upper convected Maxwell liquid towards a horizontal flat surface are addressed. The combined effect of Brownian motion and thermophoresis in nanofluid modeling are retained. The Cattaneo-Christov heat flux model is imposed. Impacts of thermal and solutal stratifications are also accounted. A set of similarity variables are utilized to form ordinary differential system from the prevailing partial differential equations. The problem of ordinary differential system is analyzed numerically through Runge-Kutta-Fehlberg based shooting method. Graphical results of pertinent parameters on the velocity, temperature and nanoparticle concentration are studied. Skin friction coefficient, local Nusselt number and Sherwood number are also addressed

Cattaneo-Christov on heat and mass transfer of unsteady Eyring Powell dusty nanofluid over sheet with heat and mass flux conditions

Heat and mass flux conditions on magnetohydrodynamic unsteady Eyring-Powell dusty nanofluid over a sheet is addressed. The combined effect of Brownian motion and thermophoresis in nanofluid modeling are retained. The Cattaneo-Christov heat flux model is imposed. A set of similarity variables are utilized to form ordinary differential system from the prevailing partial differential equations. The problem of ordinary differential system (ODS) is analyzed numerically through Runge-Kutta based shooting method. Graphical results of pertinent parameters on the velocity, temperature and nanoparticle concentration are studied. Skin friction coefficient, local Nusselt and Sherwood number are also addressed with help of graphs and also validated the present solutions with already existing solutions in the form of table. It is found that the thermal relaxation parameter improves the heat transfer rate and minimizes the mass transfer rate. The heat transfer rate is higher in prescribed heat flux (PHF) case when compared with prescribed wall temperature (PWT) case

Peripheral layer viscosity on the stenotic blood vessels for Herschel-Bulkley fluid model

This paper deals with a theoretical investigation of blood flow in an arterial fragment with the existence of stenosis. The stream-wise blood is treated as steady and it is composed of two layers (the central core and plasma). The blood is taken to be non-Newtonian liquid described with help of Herschel-Bulkley fluid model. The artery is simulated as a cylindrical tube. Flow of blood is considered as steady. An extensive quantitative exploration has been performed through numerical computations of the flow physical parameters (the velocity, mass flux and shear stress). It is found that the mass-flux reduced as the consistency of peripheral layer fluid decreases, this happens due to the enhancement of pseudo plastic nature of the blood