scispace - formally typeset
Search or ask a question

Showing papers by "Oluwole Daniel Makinde published in 2018"


Journal ArticleDOI
TL;DR: It is found that the velocity and thermal slip boundary condition showed a significant effect on momentum and thermal boundary layer thickness at the wall, and the presence of nanoparticles stabilizes the thermal boundary layers growth.
Abstract: A numerical simulation for mixed convective three-dimensional slip flow of water-based nanofluids with temperature jump boundary condition is presented. The flow is caused by nonlinear stretching surface. Conservation of energy equation involves the radiation heat flux term. Applied transverse magnetic effect of variable kind is also incorporated. Suitable nonlinear similarity transformations are used to reduce the governing equations into a set of self-similar equations. The subsequent equations are solved numerically by using shooting method. The solutions for the velocity and temperature distributions are computed for several values of flow pertinent parameters. Further, the numerical values for skin-friction coefficients and Nusselt number in respect of different nanoparticles are tabulated. A comparison between our numerical and already existing results has also been made. It is found that the velocity and thermal slip boundary condition showed a significant effect on momentum and thermal boundary layer thickness at the wall. The presence of nanoparticles stabilizes the thermal boundary layer growth.

89 citations


Journal ArticleDOI
TL;DR: In this paper, an unsteady two-dimensional magneto-hydrodynamic (MHD) boundary layer flow of an incompressible electrically conducting fluid over a slippery stretching sheet surrounded in a porous medium is reported.
Abstract: This article reports an unsteady two-dimensional Magneto-hydrodynamic (MHD) boundary layer flow of an incompressible electrically conducting fluid over a slippery stretching sheet surrounded in a porous medium. The Roseland boundary layer approximation with the radiative heat flux is employed within the current analysis. The influence of the velocity slip, thermal radiation, heat source, and buoyancy force is also considered within the current analysis, which makes significant effects on the flow field passages. The unsteady system of non-dimensional partial differential equations (PDEs) with corresponding boundary conditions are solved by implementing the explicit finite difference scheme. In the presence of pertinent parameters such as viscous dissipation, heat source or sink, Prandtl number, Grashof number, thermal radiation, magnetic field, and Darcy number, the accurate movement of the electrically conducting fluid over a slippery sheet is shown graphically in the form of velocity, temperature, skin friction coefficient, and Nusselt number. Unlike the other studies, wherein the system of PDEs is commonly transformed into a system of ordinary differential equations via the similarity transformations, the current study provides an efficient numerical procedure to solve a given system of PDEs without using the similarity transformations which exemplify the precise movement of an electrically conducting fluid over a slippery surface. It has been anticipated that the current boundary layer analysis would provide a platform for solving the system of the nonlinear PDEs of the other unsolved boundary layer models that are associated with the two-dimensional unsteady MHD flow over a slippery stretching surface embedded in a porous medium.

56 citations


Journal ArticleDOI
TL;DR: In this article, the influence of melting heat transfer and thermal stratification on a two-dimensional electrically conducting Casson fluid flow on an upper horizontal thermally stratified surface of a paraboloid of revolution is analyzed.
Abstract: Abstract Considering the recent aspiration of experts dealing with the painting of aircraft and bonnet of cars to further understand the relevance of skin friction and heat transfer while painting all these objects that are neither horizontal nor vertical, neither a cone/wedge or cylinder but upper horizontal surface of a paraboloid of revolution; a two-dimensional electrically conducting Casson fluid flow on an upper horizontal thermally stratified surface of a paraboloid of revolution is analyzed. The influence of melting heat transfer and thermal stratification are properly accounted for by modifying classical boundary condition of temperature. Plastic dynamic viscosity and thermal conductivity of the fluid are assumed to vary linearly with temperature. In view of this, all necessary models were modified to suit the case Tm

51 citations


Journal ArticleDOI
TL;DR: In this paper, the rheology of laminar incompressible Copper-Kerosene nanofluid in a channel with stretching walls under the influence of transverse magnetic field is investigated.
Abstract: In this paper, rheology of laminar incompressible Copper-Kerosene nanofluid in a channel with stretching walls under the influence of transverse magnetic field is investigated. The main structure of the partial differential equations was taken from the law of conservation of mass, momentum and energy equations. Governing boundary layer equations are transformed into nonlinear ordinary differential equations by using similarity variables and then solved with 3-stage Lobatto IIIA formula. Numerical results were compared with another numerical method (Runge-Kutta-Fehlberg) and found excellent agreement. The influence of physical parameters Reynolds number, magnetic number, solid volume fraction, momentum and thermal slip parameters on velocity and temperature profile considered. Numerical results revealed that solid volume fraction decreases the velocity of nanofluid particles near the lower wall of the channel and increase the thermal boundary layer thickness in the channel.

50 citations


Journal ArticleDOI
TL;DR: In this paper, the combined effects of wall slip, viscous dissipation, and Joule heating on MHD electro-osmotic peristaltic motion of Casson fluid with heat transfer through a rotating asymmetric micro-channel were investigated.
Abstract: In this paper, we investigate the combined effects of wall slip, viscous dissipation, and Joule heating on MHD electro-osmotic peristaltic motion of Casson fluid with heat transfer through a rotating asymmetric micro-channel. Using long wavelength and small Reynolds number assumptions, the governing equations of momentum and energy balance are obtained and tackled analytically. The effects of various embedding parameters on the stream function, velocity, temperature, skin friction, Nusselt number and trapping phenomenon are displayed graphically and discussed. It is found that Casson fluid velocity, temperature, and heat transfer rate are enhanced with a boost in electro-osmotic force.

49 citations


Journal ArticleDOI
TL;DR: It is found that Pneumonia treatment with Typhoid fever prevention costs least and the policy makers must focus more on prevention strategy while treating the infected individual is not neglected.

48 citations


Journal ArticleDOI
TL;DR: In this paper, the effect of Prandtl number on flow and heat transfer characteristics with considering the magnetic field effects is investigated, and critical Rayleigh numbers are determined for different values of physical parameters, including buoyancy term, Boussinesq approximation, and numerical solutions are obtained using the finite volume method.
Abstract: The oscillatory natural convection between two concentric cylinders is numerically investigated. The effect of Prandtl number on flow and heat transfer characteristics with considering the magnetic field effects is investigated. For different values of physical parameters, critical Rayleigh numbers are determined. For buoyancy term, the Boussinesq approximation is used, and the numerical solutions are obtained using the finite volume method. For this kind of Prandtl number, the flow and heat transfer characteristics are unique and independent of the Prandtl number. Stability diagram (RaCr-Pr) highlights the dependence of RaCr via Prandtl numbers and various Hartmann number. The importance of this modeling is its practical application for stabilizing or weakening the convective effects in the design of magnetic systems.

45 citations


Journal ArticleDOI
TL;DR: In this article, the combined impact of solar radiation, chemical reaction, Joule heating, viscous dissipation and magnetic field on flow of an electrically conducting nanofluid over a convectively heated stretching sheet embedded in a saturated porous medium is simulated.
Abstract: Abstract The combined impact of solar radiation, chemical reaction, Joule heating, viscous dissipation and magnetic field on flow of an electrically conducting nanofluid over a convectively heated stretching sheet embedded in a saturated porous medium is simulated. By using appropriate similarity transformation, the governing nonlinear equations are converted into ODEs and numerical shooting technique with (RK45) method is employed to tackle the problem. The effects of various thermo-physical parameters on the entire flow structure with heat and mass transfer are presented graphically and discussed quantitatively. Special cases of our results are benchmarked with some of those obtained earlier in the literature and are found to be in excellent agreement. It is found that both the temperature and surface concentration gradients are increasing functions of the non-Darcy porous medium parameter. One describing result is the incident solar radiation absorption and its transmission into the working nanofluid by convection.

43 citations


Journal ArticleDOI
TL;DR: In this article, the effects of thermal and exponential space dependent heat sources (THS and ESHS) on magneto-nanoliquid flow across a rotating disk with uniform stretching rate along radial direction are scrutinized in this communication.
Abstract: The effects of thermal and exponential space dependent heat sources (THS and ESHS) on magneto-nanoliquid flow across a rotating disk with uniform stretching rate along radial direction are scrutinized in this communication. H2O based nanoliquids containing aluminium (AA 7075) and titanium (Ti6Al4V) alloy nanoparticles are considered. The AA7075 is made up of 90% Al, 5-6% Zn, 2-3% Mg, 1-2% Cu with additives such as Fe, Mn and Si etc. The flow is driven due to rotating disk with uniform stretching of the disk. Impacts of Joule and viscous heating are also deployed. The multidegree ordinary differential equations are formed via Von Karman transformations. The obtained non-linear BVP is solved by Runge-Kutta-Fehlberg based shooting approach (RKFS). Graphical illustrations depict the impacts of influential parameters on flow fields. The skin friction and Nusselt number are also calculated. Results pointed out that the thermal boundary layer growth stabilizes due to the influence of ESHS aspect. Velocities of nanofluid are superior than that of nanoliquid. Furthermore, the thermal performance of base liquid is outstanding when we added titanium alloy nanoparticles in comparison with aluminium alloy nanoparticles.

35 citations


Journal ArticleDOI
TL;DR: In this article, an unbiased analysis for the unsteady two-dimensional laminar flow of an incompressible, electrically and thermally conducting fluid across the space separated by two infinite rotating permeable walls is presented.
Abstract: This article investigates an unbiased analysis for the unsteady two-dimensional laminar flow of an incompressible, electrically and thermally conducting fluid across the space separated by two infinite rotating permeable walls. The influence of entropy generation, Hall and slip effects are considered within the flow analysis. The problem is modeled based on valid physical arguments and the unsteady system of dimensionless PDEs (partial differential equations) are solved with the help of Finite Difference Scheme. In the presence of pertinent parameters, the precise movement of the flow in terms of velocity, temperature, entropy generation rate, and Bejan numbers are presented graphically, which are parabolic in nature. Streamline profiles are also presented, which exemplify the accurate movement of the flow. The current study is one of the infrequent contributions to the existing literature as previous studies have not attempted to solve the system of high order non-linear PDEs for the unsteady flow with entropy generation and Hall effects in a permeable rotating channel. It is expected that the current analysis would provide a platform for solving the system of nonlinear PDEs of the other unexplored models that are associated to the two-dimensional unsteady flow in a rotating channel.

34 citations


Journal ArticleDOI
TL;DR: In this article, optimal control theory is applied to a system o f ordinary differential equations representing a dysenter y diarrhea epidemic, and optimal control strategies are proposed to reduce the number of infected humans and the cost of inter-vions.
Abstract: In this paper, optimal control theory is applied to a system o f ordinary differential equations representing a dysenter y diarrhea epidemic. Optimal control strategies are propose d to reduce the number of infected humans and the cost of inter ventions. The Pontryagin’s maximum principle is employed to find the ne cessary conditions for the existence of the optimal control s. RungeKutta forward-backward sweep numerical approximation met hod is used to solve the optimal control system. The incremen tal costeffectiveness analysis technique is used to determine the m ost cost-effective strategy. We observe that the control me asure implementing sanitation and education campaign is the most efficient and c ost-effective.


Journal ArticleDOI
TL;DR: In this article, a theoretical investigation of a hydromagnetic boundary layer flow of Carreau fluid over a stretching cylinder with surface slippage and temperature jump is presented, where the spectral relaxation method is utilized to provide the solution of highly nonlinear system of coupled partial differential equations converted into dimensionless governing equations.
Abstract: A theoretical investigation of a hydromagnetic boundary layer flow of Carreau fluid over a stretching cylinder with surface slippage and temperature jump is presented in this paper. It is assumed that heat transfer characteristics of the flow follows Cattaneo-Christov heat flux model base on conventional Fourier’s law with thermal relaxation time. The spectral relaxation method (SRM) is being utilized to provide the solution of highly nonlinear system of coupled partial differential equations converted into dimensionless governing equations. The behaviour of flow parameters on velocity, temperature distributions are sketched as well as analyzed physically. The result indicates that the temperature distribution decay for higher temperature jump and thermal relaxation parameters respectively.

Journal ArticleDOI
01 Jun 2018
TL;DR: In this article, the heat transfer and entropy generation in a MHD flow of Casson fluid through a porous micro-channel with thermal radiation were investigated numerically by using fourth-fifth-order Runge-Kutta integration method along with shooting technique.
Abstract: The heat transfer and entropy generation in a MHD flow of Casson fluid through a porous microchannel with thermal radiation were investigated numerically. Combined effects of suction/injection, hydrodynamic slip, magnetic field and convective boundary condition on the heat transfer and entropy generation are studied. The dimensionless equations are solved numerically by using fourth-fifth-order Runge–Kutta integration method along with shooting technique. Moreover, influences of pertinent parameters on velocity, temperature and entropy generation were discussed in detail and illustrated graphically. Based on numerical results, we can see that, entropy generation rate increases with an increase in radiation parameter and Biot number. As Hartmann number increases, the entropy generation decreases at the both cooled and heated plates and increases at the centerline region of the microchannel.

Journal ArticleDOI
TL;DR: A compartmental Listeria-Anthrax coinfection model describing the transmission dynamics of Listeriosis and Anthrax epidemic in human population using the stability theory of differential equations revealed that the disease-free equilibrium of the Anthrax model only is locally stable when the basic reproduction number is less than one.
Abstract: Listeriosis and Anthrax are fatal zoonotic diseases caused by Listeria monocytogene and Bacillus Anthracis, respectively. In this paper, we proposed and analysed a compartmental Listeriosis-Anthrax coinfection model describing the transmission dynamics of Listeriosis and Anthrax epidemic in human population using the stability theory of differential equations. Our model revealed that the disease-free equilibrium of the Anthrax model only is locally stable when the basic reproduction number is less than one. Sensitivity analysis was carried out on the model parameters in order to determine their impact on the disease dynamics. Numerical simulation of the coinfection model was carried out and the results are displayed graphically and discussed. We simulate the Listeriosis-Anthrax coinfection model by varying the human contact rate to see its effects on infected Anthrax population, infected Listeriosis population, and Listeriosis-Anthrax coinfected population.

Journal ArticleDOI
TL;DR: In this article, the boundary layer flow of the fluid over an upper horizontal surface of a paraboloid of revolution is presented and the dimensional governing equations were non-dimensionalized, parameterized, solved numerically and discussed.
Abstract: The problem of fluid flow on air-jet weaving machine (i.e. mechanical engineering and chemical engineering) is deliberated upon in this report using the case of non-Newtonian Carreau fluid flow. In this report, the boundary layer flow of the fluid over an upper horizontal surface of a paraboloid of revolution is presented. The dimensional governing equations were non-dimensionalized, parameterized, solved numerically and discussed. Maximum horizontal velocity is ascertained at smaller values of thickness parameter, a larger value of buoyancy related parameter and the flow is characterized as shear-thickening. Local skin friction coefficient is an increasing and a decreasing property of Deborah number for Shear thinning and Shear-thickening cases of the flow respectively. The velocity of the flow parallel to the surface (uhspr) is a decreasing property of thickness parameter and increasing function of velocity index parameter.

Journal ArticleDOI
TL;DR: In this paper, the effect of velocity slip on hydromagnetic peristaltic flow of a Casson fluid and heat transfer through an asymmetric channel fluid filled a porous medium is examined.

Journal ArticleDOI
TL;DR: In this article, the magnetohydrodynamic flow of a Casson fluid over a permeable stretching sheet in the presence of mass transfer is studied using similarity transformations, the governing equations are converted to ordinary differential equations and then solved through MATHEMATICA.
Abstract: In this analysis, the magnetohydrodynamic flow of a Casson fluid over a permeable stretching sheet in the presence of mass transfer is studied. Using similarity transformations, the governing equations are converted to ordinary differential equations and then solved through MATHEMATICA. The skin friction coefficient and local Sherwood number are analyzed through numerical values for various parameters of interest. The velocity and concentration profiles are illustrated for several pertinent flow parameters. We observed that the Casson parameter and Hartman number have similar effects on the velocity in a qualitative sense. We further analyzed that the concentration profile decreases rapidly in comparison to the fluid velocity when we increased the values of the suction parameter.

Journal ArticleDOI
TL;DR: In this paper, an implicit finite difference technique is employed to solve the boundary layer equations in both the annular passages and the results reveal that both physical and geometrical parameters have profound influence on the development of velocity and thermal fields as well as heat transfer rate.
Abstract: The present study deals with the numerically investigation of developing laminar natural convection in the vertical double-passage porous annuli formed by three vertical concentric cylinders of which the middle cylinder is a thin and perfectly conductive known as baffle. In this analysis, two thermal conditions are considered namely, either inner or outer cylindrical wall is constantly heated while the opposite wall is insulated. An implicit finite difference technique is employed to solve the boundary layer equations in both the annular passages. The temperature profiles and velocity profiles in axial as well as radial directions have been presented for different values of Grashof number, Darcy number, baffle position and radius ratio. The results reveal that both physical and geometrical parameters have profound influence on the development of velocity and thermal fields as well as heat transfer rate.

Journal ArticleDOI
TL;DR: In this paper, a mathematical model is established to examine the influence of viscous dissipation and joule heating on magnetohydrodynamic (MHD) flow of an incompressible viscoelastic nanofluid over a convectively heated stretching sheet.
Abstract: A mathematical model is established to examine the influence of viscous dissipation and joule heating on magnetohydrodynamic (MHD) flow of an incompressible viscoelastic nanofluid over a convectively heated stretching sheet. Brownian motion and thermophoresis effects have been introduced in this nanofluid model. The governing equations are transformed into ODE’s by using suitable similarity conversions and are then solved numerically by the most robust shooting technique. The significance of numerous physical flow constraints is performed for, and distributions through graphs. It is noticed that, the increases for higher values of and reduces for rising values of heat source and Biot numbers. An outstanding contract was found between our numerical results and previously publicised results.

Journal ArticleDOI
TL;DR: In this article, the boundary layer flow and heat transfer in Casson fluid submerged with dust particles over three different geometries (vertical cone, wedge and plate) are also accounted.
Abstract: This article addresses the boundary layer flow and heat transfer in Casson fluid submerged with dust particles over three different geometries (vertical cone, wedge and plate). The aspects of Cattaneo-Christov heat flux and exponential space-based heat source (ESHS) are also accounted. At first, the partial differential equations are transformed into a set of ordinary differential equations via appropriate similarity transformations. Resulting equations are solved via shooting method coupled with the Runge-Kutta-Fehlberg-45 integration scheme. The consequences of dimensionless parameters on velocity and temperature fields of both fluid and dust particles phase are analyzed. The rate of increment/decrement in the skin friction as well as the Nusselt number for various values of physical parameters are also estimated via slope of linear regression line using data points.


Journal ArticleDOI
TL;DR: In this paper, the hydromagnetic three dimensional flow of a radiating Maxwell fluid over a stretching sheet embedded in a porous medium with heat source/sink, first ordered chemical reaction and Soret effect was numerically investigated.
Abstract: In this study, we numerically investigate the hydromagnetic three dimensional flow of a radiating Maxwell fluid over a stretching sheet embedded in a porous medium with heat source/sink, first ordered chemical reaction and Soret effect. The corresponding boundary layer equations are reduced into set of non-linear ordinary differential equations by means of similarity transformations. The resulting coupled non-linear equations are solved numerically by employing boundary value problem default solver in MATLAB bvp4c package. The obtained results are presented and discussed through graphs and tables. It is noticed that the Deborah number reduces the velocity fields and improves the temperature and concentration fields. Nomenclature

Journal ArticleDOI
TL;DR: In this paper, the problem of unsteady magnetohydrodynamic free convective flow with thermal radiation and chemical reaction past a porous vertical plate moving through a binary mixture in an optically thin environment is investigated.
Abstract: In this paper, the problem of unsteady magnetohydrodynamic free convective flow with thermal radiation and chemical reaction past a porous vertical plate moving through a binary mixture in an optically thin environment is investigated. The viscosity of the fluid is assumed to vary linearly with temperature. Due to the nature of corresponding dimensionless variable for temperature and its boundary condition as in the case of binary mixture, Boussinesq approximation and temperature dependent viscosity model were modified. The governing boundary layer equations are transformed using suitable similarity transformation and solved numerically. A parametric study of selected parameters is conducted and results for velocity, temperature, concentration, local skin friction coefficient, local Nusselt number and local Sherwood number are illustrated and physical aspects of the problem are discussed. Increasing the temperature dependent variable fluid viscosity leads to increase in the velocity of the fluid and heat transfer rate at the surface when Grashof related parameters are greater than one-tenth.

Journal ArticleDOI
TL;DR: In this article, the model equations of momentum and energy balance are obtained and transformed into ordinary differential equations using appropriate similarity variable using shooting method together with Runge-Kutta-Fehlberg numerical scheme.
Abstract: In this paper, the hydromagnetic stagnation point flow and temporal stability of Fe3O4-water ferrofluid over a convectively heated permeable stretching/shrinking sheet is theoretically investigated. The model equations of momentum and energy balance are obtained and transformed into ordinary differential equations using appropriate similarity variable. Using shooting method together with Runge-Kutta-Fehlberg numerical scheme the model nonlinear boundary value problem is tackled numerically. Pertinent results with respect to the basic steady flow velocity, temperature, skin friction and Nusselt number are obtained graphically and in tabular form. It is found that a critical value of shrinking parameter (λc) exists below which no real solution can be found. In addition, dual solutions (upper and lower branch) are observed for a range of shrinking/stretching parameter (λc<λ< 1), while for the stretching case (λ 1), the solution is unique. The obtained steady state solutions are examined for temporal development of small disturbances. The smallest eigenvalues reveal that the upper solution branch is stable and physically reliable while the lower solution branch is unstable and unrealistic. Both suction and magnetic field widen the range of the shrinking parameter for which the solution exists and boost the flow stability while nanoparticles volume fraction lessens it.

Journal ArticleDOI
TL;DR: In this paper, a theoretical investigation on MHD peristaltic flow of Newtonian and Jeffery fluid through an asymmetric channel with the effect of heat dissipation is performed.
Abstract: This is a theoretical investigation on MHD peristaltic flow of Newtonian and Jeffery fluid through an asymmetric channel with the effect of heat dissipation. The present study, we investigate to include heat dissipation, permeability, Schmidt number and heat generation parameter. The velocity, temperature and concentration profiles are performed in entire study. The governing equations are solved by using the lubrication approach and perturbation technique. The temperature, velocity and concentration fields, trapping phenomena and heat transfer coefficient are plotted by using different parameters. The significance of this study that the pressure gradient with different values of permeability gradually increased, where we observed that from the graph, the pressure gradient is lesser in Newtonian compared to the Jeffery fluid. Moreover, In the trapping phenomena the number of bolus greater in Newtonian fluid compared to the Jeffery fluid by using different values of phase difference and magnetic field parameter.

Journal ArticleDOI
TL;DR: In this article, a similarity transformation is used to convert the governing momentum and energy equations into non-linear ordinary differential equations with the relevant boundary conditions, which are solved by Duan-Rach Approach (DRA).
Abstract: Nanofluid flow and heat transfer in a rotating system between two parallel plates in the presence of thermal radiation and heat source impacts are examined. One of the plates of the considered system is penetrable and the other one is stretchable or shrinkable. A similarity transformation is used to convert the governing momentum and energy equations into non-linear ordinary differential equations with the relevant boundary conditions. The achieved non-linear ordinary differential equations are solved by Duan-Rach Approach (DRA). This method allows us to realize a solution without applying numerical methods to evaluate the unspecified coefficients. The impacts of diverse active parameters such as the stretching/shrinking parameter, the radiation parameter, the heat source parameter, the suction/blowing parameter, the Reynolds number and the volume fraction of nanofluid on the velocity and temperature profiles are explored. Also, the correlation for the Nusselt number has been developed in terms of active parameters of the present study. The outcomes indicate that the Nusselt number is a raising function of the injection parameter, nanofluid volume fraction and the radiation parameter, while it is a decreasing function of the suction and heat source parameters. Furthermore, for injection case by soaring the shrinking parameter, the probability of occurrence of the backflow phenomenon soars.

Journal ArticleDOI
TL;DR: In this paper, a two dimensional Darcy-Forchheimer steady flow of a doubly stratified Maxwell nanofluid over a sheet of continuous stretching is discussed and the system of equations of the flow are recast into a set of nonlinear ODEs which are then solved numerically by using the RKF-45 method.
Abstract: The present study discusses two dimensional Darcy-Forchheimer steady flow of a doubly stratified Maxwell nanofluid over a sheet of continuous stretching. Analysis of thermal energy and species concentration is carried out incorporating radiative heat, thermal and solutal stratifications, Brownian motion and thermophoresis. By introducing suitable transformations the system of equations of the flow are recast into a set of nonlinear ODEs which are then solved numerically by using the RKF-45 method. Flow characteristics are deliberated for different variations of governing parameters. Surface drag force, thermal energy and mass transfer rates are computed and discussed. Favourable comparisons with published work in the literature for different special cases of the problem are examined.

Journal Article
TL;DR: In this paper, the influence of non-uniform permeability, thermal radiation and variable chemical reaction on three-dimensional flow of an incompressible nanofluid over an exponentially-stretching sheet in association with a convective boundary condition has been investgated.
Abstract: The influence of non-uniform permeability, thermal radiation and variable chemical reaction on three-dimensional flow of an incompressible nanofluid over an exponentially-stretching sheet in association with a convective boundary condition has been investgated. In the present study, a new micro-convection model known as Patel model has been employed to enhance the thermal conductivity and hence the heat transfer capability of nanofluids. In the present analysis, base fluids such as water, 30% ethylene glycol, 50% ethylene glycol and nanoparticles such as Cu, Ag and Fe 3 O 4 have been considered. With the help of some suitable transformations the governing partial differential equationsare converted into a set of ordinary differential equations which have beeen then solved numerically by using fourth-order Runge-Kutta method along with shooting technique. The influence of various embedded physical parameters have been explored through graphs for velocity, temperature, concentration, skin friction, local Nusselt and Sherwood numbers. The resistive force offered by the porous matrix belittles the momentum boundary layer and helps in growing the temperature and concentration boundary layers. Fluid temperature is an increasing function of radiation parameter Rd and Biot’s number Bi whereas concentration field is a decreasing function of Schmidt number Sc and chemical reaction parameter γ.

Journal ArticleDOI
TL;DR: In this paper, a cylindrical spine fin is analyzed and the effects of parameters appearing in the boundary value problem (BVP) on temperature profile of the fin are studied.
Abstract: In this paper we analyse the heat transfer in a cylindrical spine fin. Here, both the heat transfer coefficient and thermal conductivity are temperature dependent. The resulting 2+1 dimension partial differential equation (PDE) is rendered nonlinear and difficult to solve exactly, particularly with prescribed initial and boundary conditions. We employ the three dimensional differential transform methods (3D DTM) to contract the approximate analytical solutions. Furthermore we utilize numerical techniques to determine approximate numerical solutions. The effects of parameters, appearing in the boundary value problem (BVP), on temperature profile of the fin are studied.