Blasius flow and heat transfer of fourth-grade fluid with slip

International audienceThis investigation deals with the effects of slip, magnetic field, and non-Newtonian flow parameters on the flow and heat transfer of an incompressible, electrically conducting fourth-grade fluid past an infinite porous plate. The heat transfer analysis is carried out for two heating processes. The system of highly non-linear differential equations is solved by the shooting method with the fourth-order Runge-Kutta method for moderate values of the parameters. The effective Broyden technique is adopted in order to improve the initial guesses and to satisfy the boundary conditions at infinity. An exceptional cross-over is obtained in the velocity profile in the presence of slip. The fourth-grade fluid parameter is found to increase the momentum boundary layer thickness, whereas the slip parameter substantially decreases it. Similarly, the non-Newtonian fluid parameters and the slip have opposite effects on the thermal boundary layer thickness

Mixed Convective MHD Flow of Second Grade Fluid with Viscous Dissipation and Joule Heating Past a Vertical Infinite Plate with Mass Transfer

The boundary layer flow of an unsteady, two-dimensional, laminar, mixed convective and mass transfer of a viscoelastic, incompressible and electrically conducting fluid past an infinite vertical flat plate with suction in the presence of transverse magnetic field has been analysed by taking into account the effect of viscous dissipation and Joule heating. The momentum and energy equations are reduced to couple non-linear partial differential equations along with the boundary conditions by using a suitable similarity transformation. These partial differential equations are transformed to a system of coupled non-linear ordinary differential equations by employing a perturbation technique. The system is then solved by developing a suitable numerical procedure such as fourth order Runge-Kutta method along with shooting technique. The expressions for velocity field, temperature field, concentration field and rate of heat transfer have been obtained. The results are discussed in detailed with the help of graphs and table to observe the effect of different pertinent parameters. Keywords: Second grade fluid, Joule heating, Eckert numbe

Hall current and suction/injection effects on the entropy generation of third grade fluid

In this work, effects of Hall current and suction/injection on a steady, viscous, incompressible and electrically conducting third grade fluid past a semi-infinite plate with entropy generation is investigated. It is assumed that the fluid motion is induced by applied pressure gradient. Hot fluid is injected with a constant velocity at the injection wall while it is sucked off at the upper wall with the same velocity. The governing equations of Navier-Stoke, energy and entropy generation obtained are non-dimensionalised, the resulting dimensionless velocity and temperature profiles are solved by Adomian decomposition technique due to the nonlinearity of the coupled system of equations. The obtained solution for the velocity profile is validated by the exact solution and the existing one in literature at M = 0 and the analytical expressions for fluid velocity and temperature are utilized to calculate the entropy generation and irreversibility ratio. Various plots are presented and discussed. It is found that increasing Hall current parameter increases primary velocity, temperature, entropy generation and Bejan number while the reverse trend is observed when both suction/injection and magnetic field parameters are increased. It is also noticed that entropy production at the upper wall is due to heat transfer

Heat and Mass Transfer in Radiative Casson Fluid Flow Caused by a Vertical Plate with Variable Magnetic Field Effect

The aim of the present study is to investigate influence of variable magnetic field, heat and mass transfer in radiative Casson fluid flow past an infinite vertical porous plate. The governing equations of the flow, heat and mass transfer are transformed into a system of nonlinear ordinary differential equations and solved analytically by the perturbation technique with matlab package. The results obtained show that the velocity, temperature and concentration fields are appreciably influenced by the chemical reaction, thermal stratification and magnetic field. It is observed that the thermal radiation and magnetic field decreases the velocity, temperature and concentration profiles. There is also considerable effects of magnetic field and chemical reaction on skin friction coefficient and Nusselt number. Keywords: MHD, Variable magnetic field, Radiative, Casson fluid, dissipative, Heat transfer, Mass transfer

Unsteady MHD Convective Heat And Mass Transfer Past An Infinite Vertical Plate Embedded In A Porous Medium With Radiation And Chemical Reaction Under The Influence Of Dufour And Soret Effects

A two-dimensional unsteady MHD free convective heat and mass transfer flow past a semi-infinite vertical porous plate in a porous medium in presence of thermal radiation and chemical reaction has been studied numerically including the Dufour and Soret effects. The governing nonlinear partial differential equations have been reduced to the coupled nonlinear ordinary differential equations by the similarity transformations. The resulting equations are then solved numerically using shooting method along with Runge-Kutta fourth order integration scheme. The numerical results are displayed graphically showing the effects of various parameters entering into the problem. Finally, the local values of the skin-friction coefficient, Nusselt number and Sherwood number are also shown in tabular form

Mixed convection dissipative viscous fluid flow over a rotating cone by way of variable viscosity and thermal conductivity

AbstractThe effects of temperature-dependent viscosity and thermal conductivity on the flow and heat transfer characteristics of a viscous fluid over a rotating vertical cone are premeditated. The properties of the fluid are assumed to be constant except for the density difference with the temperature. Also, the effect of viscous dissipation is considered in the energy equation. The highly nonlinear unsteady equations are converted into a system of nonlinear ordinary differential equations which is solved by using Homotopy analysis method. The interesting findings for different pertinent parameters on momentum, energy, skin friction coefficient and local Nusselt number are demonstrated in the form of graphs and tables. A comparison has been made with literature as a limiting case of the well-chosen unsteady problem

Analysis of heat transfer for unsteady MHD free convection flow of rotating Jeffrey nanofluid saturated in a porous medium

In this article, the influence of thermal radiation on unsteady magnetohydrodynamics (MHD) free convection flow of rotating Jeffrey nanofluid passing through a porous medium is studied. The silver nanoparticles (AgNPs) are dispersed in the Kerosene Oil (KO) which is chosen as conventional base fluid. Appropriate dimensionless variables are used and the system of equations is transformed into dimensionless form. The resulting problem is solved using the Laplace transform technique. The impact of pertinent parameters including volume fraction φ, material parameters of Jeffrey fluid λ1, λ, rotation parameter r, Hartmann number Ha, permeability parameter K, Grashof number Gr, Prandtl number Pr, radiation parameter Rd and dimensionless time t on velocity and temperature profiles are presented graphically with comprehensive discussions. It is observed that, the rotation parameter, due to the Coriolis force, tends to decrease the primary velocity but reverse effect is observed in the secondary velocity. It is also observed that, the Lorentz force retards the fluid flow for both primary and secondary velocities. The expressions for skin friction and Nusselt number are also evaluated for different values of emerging parameters. A comparative study with the existing published work is provided in order to verify the present results. An excellent agreement is found

Numerical Numerical of hybrid method for third grade flow due to variable accelerated plate in a rotating frame

The aim of this article is to obtain numerical solution for incompressible unsteady flow for third grade fluid induced by variable accelerated plate. Numerical solution is obtained by using Hybrid method which combine between finite difference method (FDM) and asymptotic interpolation method. The influence of difference values of material constant parameters on the velocity flow fluid are discussed and shown graphically