Oluwole Daniel Makinde

Buoyancy Effects on Thermal Boundary Layer Over a Vertical Plate With a Convective Surface Boundary Condition

This study aims to analyze the effects of thermal buoyancy on the laminar boundary layer about a vertical plate in a uniform stream of fluid under a convective surface boundary condition. Using a similarity variable, the governing nonlinear partial differential equations have been transformed into a set of coupled nonlinear ordinary differential equations, which are solved numerically by applying shooting iteration technique together with fourth-order Runge‐Kutta integration scheme. The variations in dimensionless surface temperature and fluid-solid interface characteristics for different values of Prandtl number (Pr), local Grashof number Grx, and local convective heat transfer parameter Bix are graphed and tabulated. A comparison with previously published results on special case of the problem shows excellent agreement. DOI: 10.1115/1.4001386

THE EFFECT OF THERMAL RADIATION ON THE HEAT AND MASS TRANSFER FLOW OF A VARIABLE VISCOSITY FLUID PAST A VERTICAL POROUS PLATE PERMEATED BY A TRANSVERSE MAGNETIC FIELD

The effect of temperature-dependent viscosity on free convective flow past a vertical porous plate is studied in the presence of a magnetic field, thermal radiation, and a first-order homogeneous chemical reaction. Boundary layer equations are derived and the resulting approximate nonlinear ordinary differential equations are solved numerically by the shooting method. A parametric study of all parameters involved is conducted, and a representative set of numerical results for the velocity and temperature profiles as well as the skin-friction parameter and the Nusselt and Sherwood numbers is illustrated graphically to show typical trends of the solutions. The dynamic viscosity in this study is taken as a function of the temperature although the Prandtl number is considered constant.

Effects of thermal radiation and viscous dissipation on boundary layer flow of nanofluids over a permeable moving flat plate

The effects of suction, viscous dissipation, thermal radiation and thermal diffusion are numerically studied on a boundary layer flow of nanofluids over a moving flat plate. The partial differential equations governing the motion are transformed into ordinary differential equations using similarity solutions, and are solved using the Runge–Kutta–Fehlberg method with the shooting technique. The effects of nanoparticle volume fraction, the type of nanoparticles, the radiation parameter, the Brinkman number, the suction/injection parameter and the relative motion of the plate on the nanofluids velocity, temperature, skin friction and heat transfer characteristics are graphically presented and then discussed quantitatively. A comparative study between the previously published and the present results in a limiting sense reveals excellent agreement between them.

On MHD boundary‐layer flow and mass transfer past a vertical plate in a porous medium with constant heat flux

Purpose – The hydromagnetic mixed convection flow of an incompressible viscous electrically conducting fluid and mass transfer over a vertical porous plate with constant heat flux embedded in a porous medium is investigated.Design/methodology/approach – Using the Boussinesq and boundary‐layer approximations, the fluid equations for momentum, energy balance and concentration governing the problem are formulated. These equations are solved numerically by using the most effective Newton–Raphson shooting method along with fourth‐order Runge–Kutta integration algorithm.Findings – It was found that for positive values of the buoyancy parameters, the skin friction increased with increasing values of both the Eckert number (Ec) and the magnetic field intensity parameter (M) and decreased with increasing values of both the Schmidt number (Sc) and the permeability parameter (K).Practical implications – A very useful source of information for researchers on the subject of hydromagnetic flow in porous media.Originali...

Adomian decomposition approach to a SIR epidemic model with constant vaccination strategy

Over the years, diligent vaccination campaigns have resulted in high levels of permanent immunity against the childhood disease among the population. In this article, a SIR model that monitors the temporal dynamics of a childhood disease in the presence of preventive vaccine is developed. The qualitative analysis reveals the vaccination reproductive number for disease control and eradication. Adomian decomposition method is also employed to compute an approximation to the solution of the non-linear system of differential equations governing the problem. Maple is used to carry out the computations. Graphical results are presented and discussed quantitatively to illustrate the solution.

UNSTEADY MIXED CONVECTION WITH SORET AND DUFOUR EFFECTS PAST A POROUS PLATE MOVING THROUGH A BINARY MIXTURE OF CHEMICALLY REACTING FLUID

This study investigates the unsteady mixed convection flow past a vertical porous flat plate moving through a binary mixture in the presence of radiative heat transfer and nth-order Arrhenius type of irreversible chemical reaction by taking into account the diffusion-thermal (Dufour) and thermo-diffusion (Soret) effects. Assuming an optically thin radiating fluid and using a local similarity variable, the governing nonlinear partial differential equations have been transformed into a set of coupled nonlinear ordinary differential equations, which are solved numerically by applying shooting iteration technique together with fourth-order Runge-Kutta integration scheme. Graphical results for the dimensionless velocity, temperature, and concentration distributions are shown for various values of the thermophysical parameters controlling the flow regime. Finally, numerical values of physical quantities, such as the local skin-friction coefficient, the local Nusselt number, and the local Sherwood number are presented in tabular form.

Computational modelling of MHD unsteady flow and heat transfer toward a flat plate with Navier slip and Newtonian heating

The combined effects of Navier slip and Newtonian heating on an unsteady hydromagnetic boundary layer stagnation point flow towards a flat plate in the presence of a magnetic field are studied. The self-similar equations are obtained using similarity transformations and solved numerically by a shooting algorithm with a Runge-Kutta Fehlberg integration scheme. The velocity profiles, temperature profiles, the local skin friction coefficient, and the local Nusselt number are computed and discussed in details for various values of the different parameters. Numerical results are presented both in tabular and graphical forms, illustrating the effects of these parameters on the thermal and concentration boundary layers. It is revealed that the thermal boundary layer thickens with a rise in the flow unsteadiness and as Newtonian heating intensifies, while the local skin friction and the rate of heat transfer at the plate surface change significantly due to the slip parameter.

MHD MIXED-CONVECTION INTERACTION WITH THERMAL RADIATION AND nTH ORDER CHEMICAL REACTION PAST A VERTICAL POROUS PLATE EMBEDDED IN A POROUS MEDIUM

This article investigates the hydromagnetic mixed convection heat and mass transfer flow of an incompressible Boussinesq fluid past a vertical porous plate with constant heat flux in the presence of radiative heat transfer in an optically thin environment, viscous dissipation, and an nth order homogeneous chemical reaction between the fluid and the diffusing species. The dimensionless governing equations for this investigation are solved numerically by the fourth-order Runge-Kutta integration scheme along with shooting technique. Numerical data for the local skin-friction coefficient, the plate surface temperature, and the local Sherwood number have been tabulated for various values of parametric conditions. Graphical results for velocity, temperature, and concentration profiles based on the numerical solutions are presented and discussed.

Magnetohydrodynamic Mixed-Convective Flow and Heat and Mass Transfer Past a Vertical Plate in a Porous Medium With Constant Wall Suction

The problem of steady laminar hydromagnetic heat transfer by mixed convection flow over a vertical plate embedded in a uniform porous medium in the presence of a uniform normal magnetic field is studied. Convective heat transfer through porous media has wide applications in engineering problems such as in high temperature heat exchangers and in insulation problems. We construct solutions for the free convection boundary-layer flow equations using an Adomian–Pade approximation method that in the recent past has proven to be an able alternative to the traditional numerical techniques. The effects of the various flow parameters such as the Eckert, Hartmann, and Schmidt numbers on the skin friction coefficient and the concentration, velocity, and temperature profiles are discussed and presented graphically. A comparison of our results with those obtained using traditional numerical methods in earlier studies is made, and the results show an excellent agreement. The results demonstrate the reliability and the efficiency of the Adomian–Pade method in an unbounded domain.

Effects of viscous dissipation and Newtonian heating on boundary-layer flow of nanofluids over a flat plate

Purpose – The purpose of this paper is to investigate the combined effects of viscous dissipation and Newtonian heating on boundary-layer flow over a flat plate for three types of water-based nanofluids containing metallic or nonmetallic nanoparticles such as copper (Cu), alumina (Al2O3), and titania (TiO2) for a range of nanoparticle volume fractions. Design/methodology/approach – The governing partial differential equations are transformed into ordinary differential equations using a similarity transformation, before being solved numerically by a Runge-Kutta-Fehlberg method with shooting technique. Findings – It is found that the heat transfer rate at the plate surface increases with increasing nanoparticle volume fraction and Biot number, while it decreases with the Brinkmann number. Moreover, the heat transfer rate at the plate surface with Cu-water nanofluid is higher than that of Al2O3-water and TiO2-water nanofluids. Practical implications – The heat transfer enhancement performances presented by n...