Browsing by Author "Makinde, O. D."
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- ItemAnalysis of heat transfer in Berman flow of nanofluids with Navier slip, viscous dissipation, and convective cooling(Hindawi Publishing Corporation, 2014-03-31) Makinde, O. D.; Khamis, S.; Tshehla, M. S.; Franks, O.Heat transfer characteristics of a Berman flow of water based nanofluids containing copper (Cu) and alumina (Al2O3) as nanoparticles in a porous channel with Navier slip, viscous dissipation, and convective cooling are investigated. It is assumed that the exchange of heat with the ambient surrounding takes place at the channel walls following Newton’s law of cooling. The governing partial differential equations and boundary conditions are converted into a set of nonlinear ordinary differential equations using appropriate similarity transformations. These equations are solved analytically by regular perturbation methods with series improvement technique and numerically using an efficient Runge-Kutta Fehlberg integration technique coupled with shooting scheme.The effects of the governing parameters on the dimensionless velocity, temperature, skin friction, pressure drop, and Nusselt numbers are presented graphically and discussed quantitatively.
- ItemAnalysis of thermal stability in a convecting and radiating two-step reactive slab(Hindawi, 2013) Makinde, O. D.; Tshehla, M. S.This paper investigates the combined effects of convective and radiative heat loss on thermal stability of a rectangular slab of combustible materials with internal heat generation due to a two-step exothermic chemical reaction, taking the diffusion of the reactant into account and assuming a variable (temperature dependent) preexponential factor. The nonlinear differential equation governing the transient reaction-diffusion problem is obtained and tackled numerically using a semidiscretization finite difference technique. A special type of Hermite-Pade approximants coupled with perturbation technique are employed to analyze the effects of ´ various embedded thermophysical parameters on the steady state problem. Important properties of the temperature field including thermal stability conditions are presented graphically and discussed quantitatively.
- ItemApplication of successive linearisation method to squeezing flow with bifurcation(Hindawi Publishing Corporation, 2014-01-02) Motsa, S. S.; Makinde, O. D.; Shateyi, S.This paper employs the computational approach known as successive linearization method (SLM) to tackle a fourth order nonlinear differential equation modelling the transient flow of an incompressible viscous fluid between two parallel plates produced by a simple wall motion. Numerical and graphical results obtained show excellent agreement with the earlier results reported in the literature. We obtain solution branches as well as a turning point in the flow field accurately. A comparison with numerical results generated using the inbuilt MATLAB boundary value solver, bvp4c, demonstrates that the SLM approach is a very efficient technique for tackling highly nonlinear differential equations of the type discussed in this paper.
- ItemComputational dynamics of arterial blood flow in the presence of magnetic field and thermal radiation therapy(Hindawi Publishing Corporation, 2014-04-22) Chinyoka, T.; Makinde, O. D.We conduct a numerical study to determine the influence of magnetic field and thermal radiation on both velocity and temperature distributions in a single blood vessel. The model here assumes that blood is a Newtonian incompressible conducting fluid with radially varying viscosity due to hematocrit variation. The transient equations of momentum and energy transport governing the flow in an axisymmetric configuration are solved numerically using a semi-implicit finite difference method. Results are presented graphically and discussed both qualitatively and quantitatively from the physiological point of view. The results of this work may enhance current understanding of the factors that determine the effects of hyperthermia treatment on tumor tissues.
- ItemComputational modelling and optimal control of Ebola virus disease with non-linear incidence rate(IOP Publishing, 2017) Takaidza, I.; Makinde, O. D.; Okosun, O. K.The 2014 Ebola outbreak in West Africa has exposed the need to connect modellers and those with relevant data as pivotal to better understanding of how the disease spreads and quantifying the effects of possible interventions. In this paper, we model and analyse the Ebola virus disease with non-linear incidence rate. The epidemic model created is used to describe how the Ebola virus could potentially evolve in a population. We perform an uncertainty analysis of the basic reproductive number R 0 to quantify its sensitivity to other disease-related parameters. We also analyse the sensitivity of the final epidemic size to the time control interventions (education, vaccination, quarantine and safe handling) and provide the cost effective combination of the interventions.
- ItemComputational modelling and similarity reduction of equations for transient fluid flow and heat transfer with variable properties(Hindawi, 2013) Moitsheki, R. J.; Makinde, O. D.We consider a system of coupled partial differential equations describing transient fluid flow and heat transfer with variable flow properties. Classical Lie point symmetry analysis of this system resulted in admitted large Lie algebras for some special cases of the arbitrary constants and the source term. Symmetry reductions are performed and as such the system of partial differential equations is reduced to the system of ordinary differential equations. Some reduced ordinary differential equation could be solved exactly with restrictions on the parameters appearing in it. In addition, shooting quadrature is employed to numerically tackle the nonlinear model boundary value problem and pertinent results are presented graphically and discussed quantitatively
- ItemEffects of thermal radiation on MHD peristaltic motion of walters-B fluid with heat source and slip conditions(Regional Information Center for Science and Technology, 2017) Makinde, O. D.; Reddy, M. Gnaneswara; Reddy, K. VenugopalIn this paper, we examine the combined effects of magnetic field, thermal radiation, heat source, velocity slip and thermal jump on peristaltic transport of an electrically conducting Walters-B fluid through a compliant walled channel. Using small wave number approach, the nonlinear model differential equations are obtained and tackled analytically by regular perturbation method. Expressions for the stream function, velocity, temperature, skin-friction coefficient and heat transfer coefficient are constructed. Pertinent results are presented graphically and discussed quantitatively. It is found that the velocity distribution depresses while the fluid temperature rises with an increase in Hartmann number. The trapping phenomenon is observed and the size of trapped bolus increases with an increase in Hartmann number.
- ItemEMHD flow of non-Newtonian nanofluids over thin needle with Robinson’s condition and Arrhenius pre-exponential factor law(IOP Science, 2020-10-21) Mabood, Fazle; Muhammad, Taseer; Nayak, M. K.; Waqas, Hassan; Makinde, O. D.Many researchers and scientists are devoting their time to scrutinize nanofluids nature and characteristics for heat transfer enhancement. The scrutiny of nanoliquids is important in the large scale thermal management systems via evaporators, advanced cooling systems, heat exchangers, micro/nano-electromechanical devices and industrial chilling applications. Nanoliquids are very momentous even in the natural process via different fields like chemistry, chemical engineering, physics and biology. Nanoliquids can be utilized in various fields of engineering such as different chemical procedures, cooling of electronic equipment and heat exchangers. The main aim of current article is to scrutinize electromagnetohydrodynamic flow of micropolar-Casson-Carreau nanoliquids over thin needle with Robinson's conditions and Arrhenius pre-exponential factor law. Double stratification effects are also taken into account. The reverent partial differential equations are reformulated into the system of ordinary differential expressions by implementing appropriate transformations. Such obtained equations subject to boundary constraints are computed numerically by considering Runge–Kutta-Fehlberg method. Behaviour of numerous interesting parameters on flow fields is deliberated. The outcomes of flow fields are delineated through graphs and tabular data.
- ItemHeat and mass transfer analysis of MHD peristaltic flow through a complaint porous channel with variable thermal conductivity(IOP Science, 2020-02-18) Vaidya, H.; Rajashekhar, C.; Manjunatha, G.; Prasad, K. V.; Makinde, O. D.; Vajravelu, K.The MHD peristaltic motion of Bingham fluid through a uniform channel is examined under the influence of long wavelength and small Reynolds number. The impact of variable thermal conductivity, convective heat transfer, porous boundaries, and wall properties are considered. The semi-analytical technique is utilized to solve the governing nonlinear temperature equation. The effects of different parameters on the physiological quantities of interest are captured with the assistance of MATLAB programming. The assessment reveals that an ascent in a magnetic parameter reduces the velocity field. Further, an increment in the estimation of variable thermal conductivity upgrades the temperature profiles. Besides, the trapped bolus is a function of a porous parameter, and an increase in porous parameter will have the proportional increment in the other parameter.
- ItemHeat transfer to MHD oscillatory dusty fluid flow in a channel filled with a porous medium(Indian Academy of Sciences, 2015) Prakash, O. M.; Makinde, O. D.; Kumar, Devendra; Dwivedi, Y. K.In this paper, we examine the combined effects of thermal radiation, buoyancy force and magnetic field on oscillatory flow of a conducting optically thin dusty fluid through a vertical channel filled with a saturated porous medium. The governing partial differential equations are obtained and solved analytically by variable separable method. Numerical results depicting the effects of various embedded parameters like radiation number, Hartmann number and Grashof number on dusty fluid velocity profiles, temperature profiles, Nusselt number and skin friction coefficient are presented graphically and discussed qualitatively.
- ItemIrreversibility analysis of hydromagnetic flow of couple stress fluid with radiative heat in a channel filled with a porous medium(Elsevier, 2017) Eegunjobi, A. S.; Makinde, O. D.Numerical analysis of the intrinsic irreversibility of a mixed convection hydromagnetic flow of an electrically conducting couple stress fluid through upright channel filled with a saturated porous medium and radiative heat transfer was carried out. The thermodynamics first and second laws were employed to examine the problem. We obtained the dimensionless nonlinear differential equations and solves numerically with shooting procedure joined with a fourth order Runge-Kutta-Fehlberg integration scheme. The temperature and velocity obtained, used to analyse the entropy generation rate together with some various physical parameters of the flow. Our results are presented graphically and talk over.
- ItemMHD slip flow and heat transfer over an exponentially stretching permeable sheet embedded in a porous medium with heat source(Global Digital Central, 2017) Sharma, P. R.; Choudhary, Sushila; Makinde, O. D.Steady two dimensional laminar magnetohydrodynamic (MHD) slip flow and heat transfer of a viscous incompressible and electrically conducting fluid past over a flat exponentially non-conducting stretching porous sheet embedded in a porous medium with non uniform permeability in the presence of non uniform heat source is investigated. The governing equations of velocity and temperature distributions are solved numerically and the effects of different physical parameters are shown through graphs. The rate of shear stress and the rate of heat transfer at the sheet are derived, discussed numerically and their numerical values for various values of physical parameters are presented through tables.
- ItemNatural convection of viscoelastic fluid from a cone embedded in a porous medium with viscous dissipation(Hindawi, 2013) Makanda, Gilbert; Makinde, O. D.; Sibanda, PreciousWe study natural convection from a downward pointing cone in a viscoelastic fluid embedded in a porous medium. The fluid properties are numerically computed for different viscoelastic, porosity, Prandtl and Eckert numbers.The governing partial differential equations are converted to a system of fourth order ordinary differential equations using the similarity transformations and then solved together by using the successive linearizationmethod (SLM).Many studies have been carried out on natural convection from a cone but they did not consider a cone embedded in a porous medium with linear surface temperature. The results in this work are validated by the comparison with other authors.
- ItemNumerical investigation into entropy generation in a transient generalized Couette flow of nanofluids with convective cooling(Indian Academy of Sciences, 2015) Mkwizu, M. H.; Makinde, O. D.; Nkansah-Gyekye, YawThis work investigates the effects of convective cooling on entropy generation in a transient generalized Couette flow of water-based nanofluids containing Copper (Cu) and Alumina (Al 2O3) as nanoparticles. Both First and Second Laws of thermodynamics are utilised to analyse the problem. The model partial differential equations for momentum and energy balance are tackled numerically using a semi-discretization finite difference method together with Runge–Kutta Fehlberg integration scheme. Graphical results on the effects of parameter variation on velocity, temperature, skin friction, Nusselt number, entropy generation rate, irreversibility ratio and Bejan number are presented and discussed.
- ItemOn new high order quasilinearization approaches to the nonlinear model of catalytic reaction in a flat particle(Hindawi Publishing Corporation, 2013) Motsa, S. S.; Makinde, O. D.; Shateyi, S.A novel computational approach known as pseudospectral quasilinearization (SQLM) is employed to tackle the two-point boundary value problem describing the reactivity behaviour of porous catalyst particles subject to both internal mass concentration gradients and temperature gradients, in endothermic or exothermic catalytic reactions. A comparison with the numerical results generated using the inbuilt MATLAB boundary value solver, bvp4c, for different values of the governing physical parameters is performed and an excellent agreement is achieved. A systematic way of improving the convergence of the SQLM is also presented.
- ItemParabolic curve fitting study subject to Joule heating in MHD thermally stratified mixed convection stagnation point flow of Eyring-Powell fluid induced by an inclined cylindrical surface(Elsevier, 2018) Rehman, Khalil-Ur; Malik, M. Y.; Makinde, O. D.The current analysis is carried out to envision the properties of magneto-hydrodynamic boundary layer stagnation point flow of Eyring-Powell (non-Newtonian) fluid induced by an inclined stretching cylindrical surface in the presence of both mixed convection and Joule heating effects. Flow analysis is manifested with temperature stratification phenomena. The strength of temperature adjacent to the cylindrical surface is assumed to be higher in strength as compared to the ambient fluid. A suitable similarity transformations are utilized to convert the flow conducting equations (mathematically modelled) into system of coupled non-linear ordinary differential equations. A fifth order Runge-Kutta algorithm charted with shooting scheme is used to trace out the numerical additions. It was found that the velocity profile is an increasing function of both mixed convection and curvature parameters. Temperature profile show inciting nature towards Eckert number. In addition, a straight line and parabolic curve fitting way of study is executed to inspect the effect logs of mixed convection parameter, magnetic field parameter, thermal stratification parameter and heat generation parameter on skin friction coefficient and heat rate. It seems to be first attempt in this direction and will serve as a facilitating source for the preceding studies regarding fluid rheology.
- ItemSoret and Dufour effects on MHD flow with heat and mass transfer past a permeable stretching sheet in presence of thermal radiation(NISCAIR-CSIR, 2017) Sreedevi, G.; Rao, D. R. V. Prasada; Makinde, O. D.; Reddy, G. Venkata RamanaAn analysis has been carried out to study the combined effects of the magnetic field, Joule heating, thermal radiation absorption, viscous dissipation, Buoyancy forces, thermal-diffusion and diffusion-thermion the convective heat and mass transfer flow of an electrically conducting fluid over a permeable vertically stretching sheet. The boundary layer equations for the fluid flow, heat and mass flux under consideration have been obtained and reduced into a system of non-linear ordinary differential equations by using appropriate similarity transformation. Using shooting method coupled with the fourth order Runge-Kutta integration scheme, the numerically solutions have been obtained and presented graphically. The effects of various embedded thermo-physical parameters on the fluid velocity, temperature, skin friction, Nusselt number and Sherwood number have been determined and discussed quantitatively. A comparison of a special case of our results with the one previously reported in the literature shows a very good agreement. An increase in values of thermal radiation, viscous dissipation, suction/injection coefficient and chemical reaction results in the increase of velocity, temperature and heat-mass transfer rates. It is further noted that the velocity, temperature and heat-mass transfer rates reduces on the boundary layer of a permeable vertical stretching sheet due to increase in the values of Soret or decrease in values of Dufour. Further, this work leads to study different flows of electrically conducting fluid over a permeable vertical stretching sheet problem that includes the two dimensional non-linear boundary equations.
- ItemThermophoresis and Brownian Motion Effects on Magnetohydrodynamics Electro-Osmotic Jeffrey Nanofluid Peristaltic Flow in Asymmetric Rotating Microchannel(American Scientific Publishers, 2019-03) Reddy, K. Venugopal; Reddy, M. Gnaneswara; Makinde, O. D.This article investigates with the thermophoresis and Brownian motion effects on MHD electro-osmotic Jeffrey nanofluid peristaltic flow in an asymmetric microchannel. Well established large wavelength and small Reynolds number approximations are invoked. Numerical solutions have been evaluated for the stream function, nanofluid velocity, nanofluid temperature and nanoparticle phenomena. The computed results for nanofluid velocity, temperature, and concentration fields are utilized to determine the skin-friction, Nusselt number, and Sherwood number. The graphical results have been presented and discussed for various involved parameters. The novel features of nanofluids made them potentially significant in heat and mass transfer mechanism occurring in medical and industrial processes like microelectronics, pharmaceutical processes, hybrid engines, thermal management of vehicles, refrigerator, chiller, gas temperature reduction and so forth. These processes bear tendency to enhance thermal conductivity and the convective heat transfer more efficiently than base fluid. This unique aspect made nanofluids the topic of interest in recent time via different fluid flow models. The problem at hand is one such application of nanofluids in peristaltic flow through the asymmetric rotating microchannel.
- ItemUnsteady hydromagnetic flow of radiating fluid past a convectively heated vertical plate with the Navier slip(Hindawi Publishing Corporation, 2014-04-17) Makinde, O. D.; Tshehla, M. S.This paper investigates the unsteady hydromagnetic-free convection of an incompressible electrical conducting Boussinesq’s radiating fluid past a moving vertical plate in an optically thin environment with the Navier slip, viscous dissipation, and Ohmic and Newtonian heating. The nonlinear partial differential equations governing the transient problem are obtained and tackled numerically using a semidiscretization finite difference method coupled with Runge-Kutta Fehlberg integration technique. Numerical data for the local skin friction coefficient and the Nusselt number have been tabulated for various values of parametric conditions. Graphical results for the fluid velocity, temperature, skin friction, and the Nusselt number are presented and discussed. The results indicate that the skin friction coefficient decreases while the heat transfer rate at the plate surface increases as the slip parameter and Newtonian heating increase.