In this work, an analytical study is carried out on double-diffusive natural convection through a horizontal anisotropic porous layer saturated with a non-Newtonian fluid by using the Darcy model with the Boussinesq a...In this work, an analytical study is carried out on double-diffusive natural convection through a horizontal anisotropic porous layer saturated with a non-Newtonian fluid by using the Darcy model with the Boussinesq approximations. The horizontal walls of the system are subject to vertical uniform fluxes of heat and mass, whereas the vertical walls are assumed to be adiabatic and impermeable. The Soret effect is taken into consideration. Based on parallel flow approximation theory, the problem is solved in the limit of a thin layer and documented the effects of the physical parameters describing this investigation.展开更多
This paper studies the thermal-diffusion and diffusion thermo-effects in the hydro-magnetic unsteady flow by a mixed convection boundary layer past an imperme- able vertical stretching sheet in a porous medium in the ...This paper studies the thermal-diffusion and diffusion thermo-effects in the hydro-magnetic unsteady flow by a mixed convection boundary layer past an imperme- able vertical stretching sheet in a porous medium in the presence of chemical reaction. The velocity of t^he stretching surface, the surface temperature, and the concentration are assumed to vary linearly with the distance along the surface. The governing partial differential equations are transformed into self-similar unsteady equations using similarity transformations .and solved numerically by the Runge-Kutta fourth order scheme in as- sociation with the shooting method for the whole transient domain from the initial state to the final steady state flow. Numerical results for the velocity, the temperature, the concentration, the skin friction, and the Nusselt and Sherwood numbers are shown graph- ically for various flow parameters. The results reveal that there is a smooth transition of flow from unsteady state to the final steady state. A special case of our results is in good agreement with an earlier published work.展开更多
The objective of the present study is to investigate the effect of flow parameters on the free convection and mass transfer of an unsteady magnetohydrodynamic flow of an electrically conducting, viscous, and incompres...The objective of the present study is to investigate the effect of flow parameters on the free convection and mass transfer of an unsteady magnetohydrodynamic flow of an electrically conducting, viscous, and incompressible fluid past an infinite vertical porous plate under oscillatory suction velocity and thermal radiation. The Dufour (diffusion thermo) and Soret (thermal diffusion) effects are taken into account. The problem is solved numerically using the finite element method for the velocity, the temperature, and the concentration field. The expression for the skin friction, the rate of heat and mass transfer is obtained. The results are presented numerically through graphs and tables for the externally cooled plate (Gr 〉 0) and the externally heated plate (Gr 〈 0) to observe the effects of various parameters encountered in the equations.展开更多
In this work, the Micropolar fluid flow and heat and mass transfer past a horizontal nonlinear stretching sheet through porous medium is studied including the Soret-Dufour effect in the presence of suction. A uniform ...In this work, the Micropolar fluid flow and heat and mass transfer past a horizontal nonlinear stretching sheet through porous medium is studied including the Soret-Dufour effect in the presence of suction. A uniform magnetic field is applied transversely to the direction of the flow. The governing differential equations of the problem have been transformed into a system of non-dimensional differential equations which are solved numerically by Nachtsheim-Swigert iteration technique along with the sixth order Runge-Kutta integration scheme. The velocity, microrotation, temperature and concentration profiles are presented for different parameters. The present problem finds significant applications in hydromagnetic control of conducting polymeric sheets, magnetic materials processing, etc.展开更多
An analysis of two-dimensional steady magneto-hydrodynamic free convection flow of an electrically conducting, viscous, incompressible fluid past an inclined stretching porous plate in the presence of a uniform magnet...An analysis of two-dimensional steady magneto-hydrodynamic free convection flow of an electrically conducting, viscous, incompressible fluid past an inclined stretching porous plate in the presence of a uniform magnetic field and thermal radiation with heat generation is made. Both the Dufour and Soret effects are considered for a hydrogen-air mixture as the non-chemically reacting fluid pair. The equations governing the flow, temperature and concentration fields are reduced to a system of joined non-linear ordinary differential equations by similarity transformation. Non-linear differential equations are integrated numerically by using Nachtsheim-Swigert shooting iteration technique along with sixth order Runge-Kutta integration scheme. Finally the significance of physical parameters which are of engineering interest are examined both in graphical and tabular form.展开更多
This work aims to study the nonlinear ordinary differential equations(ODEs)system of magnetohydrodynamic(MHD)past over an inclined plate using Levenberg-Marquardt backpropagation neural networks(LMBNNs).The stochastic...This work aims to study the nonlinear ordinary differential equations(ODEs)system of magnetohydrodynamic(MHD)past over an inclined plate using Levenberg-Marquardt backpropagation neural networks(LMBNNs).The stochastic procedures LMBNNs are provided with three categories of sample statistics,testing,training,and verification.The nonlinear MHD system past over an inclined plate is divided into three profiles,dimensionless momentum,species(salinity),and energy(heat)conservations.The data is applied 15%,10%,and 75%for validation,testing,and training to solve the nonlinear system of MHD past over an inclined plate.A reference data set is designed to compare the obtained and proposed solutions for the MHD system.The plots of the absolute error(AE)are provided to check the accuracy and precision of the considered nonlinear system of MHD.The obtained numerical solutions of the nonlinear magnetohydrodynamic system have been considered to reduce the mean square error(MSE).For the capability,dependability,and aptitude of the stochastic LMBNNs procedure,the numerical performances are provided to authenticate the relative arrangements of MSE,error histograms(EHs),state transitions(STs),correlation,and regression.展开更多
We made an elaborate scrutiny on the Soret and Joule effects of MHD mixed convective flow of an incompressible and electrically conducting viscous fluid past an infinite vertical porous plate taking Hall effects into ...We made an elaborate scrutiny on the Soret and Joule effects of MHD mixed convective flow of an incompressible and electrically conducting viscous fluid past an infinite vertical porous plate taking Hall effects into account.Perturbation technique is used to solve the non-dimensional equations.The effects of the various non-dimensional parameters on velocity,temperature and concentration within the boundary layer are examined.Besides that,computational deliberations or discussions are also undertaken on the effects of the pertinent or significant parameters on the skin-friction coefficient and rates of heat and mass transfer in terms of the Nusselt and Sherwood numbers respectively.The concentration distribution increases with increase in Soret effect and decrease with increase in chemical reaction parameter.An increase in Prandtl number results to decrease the temperature distribution.Both the primary and secondary velocity components and temperature increases with increasing heat source parameter.Skin friction coefficient decreases with an increase in permeability parameter,whereas it shows reverse effect for thermal and mass Grashof numbers.Nusselt number increases with an increase in Prandtl number.Sherwood number reduces with increasing Soret number.展开更多
This article inspects the effect of triple diffusion in a vertical conduit encapsulated with porous matrix and subjected to third kind boundary conditions.Third kind boundary condition is a combination of Dirichlet an...This article inspects the effect of triple diffusion in a vertical conduit encapsulated with porous matrix and subjected to third kind boundary conditions.Third kind boundary condition is a combination of Dirichlet and Neumann boundary conditions which specifies a linear combination of function and its derivative values on the boundary.Homogeneous chemical reaction along with viscous and Darcy dissipation effects are included.Adapting the Boussinesq approximation,the soultal buoyancy effects due to concentration gradients of the dispersed components are taken into account.Applying suitable transformations,the conservation equations are reduced into dimensionless form and the dimensionless parameters evolved are thermal Grashof number (0≤Λ_(1)≤20),solutal Grashof number(for species 1 and 2,0≤Λ_(2);Λ_(3)≤20),porous (2≤σ≤8) and inertial parameters (0≤Ι≤6),Biot numbers(at the left and right walls,1≤Bi_(1);Bi_(2)≤10),Brinkman number (0≤Br≤1),Schmidt numbers (0≤Sc_(1);Sc_(2)≤6),Soret numbers (Sr_(1) =Sr_(2) =1) and temperature difference ratio (R_(T) = 1).Adopting perturbation technique,the analytical solutions which are applicable only when the Brinkman number is less than one is appraised.However for any values of the Brinkman number,Runge-Kutta shooting method is operated.The impact of selected parameters on the momentum,heat and dual species concentration fields are presented in the form of pictures.The solutions computed by numerical method are justified by comparing with the analytical method.The numerical and analytical solutions are equal in the absence of Darcy and viscous dissipations and the discrepancy advances as the Brinkman number expands.Further the solutions obtained are also justified by comparing the results with Zanchini[1]in the absence of chemical reaction for clear fluid.The thermal field is augmented with the Brinkman number for symmetric and asymmetric Biot numbers.However the profiles are highly distinct at the cold plate for unequal Biot numbers in comparison with equal Biot numbers.The conclusions are admissible to materials processing and chemical transport phenomena.展开更多
The magnetic impacts upon the transport of heat and mass of an electrically conducting nanofluid within an annulus among an inner rhombus with convex and outer cavity with periodic temperature/concentration profiles o...The magnetic impacts upon the transport of heat and mass of an electrically conducting nanofluid within an annulus among an inner rhombus with convex and outer cavity with periodic temperature/concentration profiles on its left wall are assessed by the ISPH method.The right wall has Tcand C,cflat walls are adiabatic,and the temperature and concentration of the left wall are altered sinusoidally with time.The features of the heat and mass transfer and fluid flow through an annulus are assessed across a wide scale of Hartmann number Ha,Soret number Sr,oscillation amplitude A,Dufour number Du,nanoparticles parameterΦ,oscillation frequency f,Rayleigh number Ra,and radius of a superellipse a at Lewis number Le=20,magnetic field’s angle g=45°,Prandtl number Pr=6.2,a superellipse coefficient n=3/2,and buoyancy parameter N=1.The results reveal that the velocity’s maximum reduces by 70.93%as Ha boosts from 0 to 50,and by 66.24%as coefficient a boosts from 0.1 to 0.4.Whilst the velocity’s maximum augments by 83.04%as Sr increases from 0.6 to 2 plus a decrease in Du from 1 to0.03.The oscillation amplitude A,and frequency f are significantly affecting the nanofluid speed,and heat and mass transfer inside an annulus.Increasing the parameters A and f is augmenting the values of mean Nusselt number-(Sh)and mean Sherwood number^-(Nu).Increasing the radius of a superellipse a enhances the values of^(Nu)and^(Sh).展开更多
文摘In this work, an analytical study is carried out on double-diffusive natural convection through a horizontal anisotropic porous layer saturated with a non-Newtonian fluid by using the Darcy model with the Boussinesq approximations. The horizontal walls of the system are subject to vertical uniform fluxes of heat and mass, whereas the vertical walls are assumed to be adiabatic and impermeable. The Soret effect is taken into consideration. Based on parallel flow approximation theory, the problem is solved in the limit of a thin layer and documented the effects of the physical parameters describing this investigation.
文摘This paper studies the thermal-diffusion and diffusion thermo-effects in the hydro-magnetic unsteady flow by a mixed convection boundary layer past an imperme- able vertical stretching sheet in a porous medium in the presence of chemical reaction. The velocity of t^he stretching surface, the surface temperature, and the concentration are assumed to vary linearly with the distance along the surface. The governing partial differential equations are transformed into self-similar unsteady equations using similarity transformations .and solved numerically by the Runge-Kutta fourth order scheme in as- sociation with the shooting method for the whole transient domain from the initial state to the final steady state flow. Numerical results for the velocity, the temperature, the concentration, the skin friction, and the Nusselt and Sherwood numbers are shown graph- ically for various flow parameters. The results reveal that there is a smooth transition of flow from unsteady state to the final steady state. A special case of our results is in good agreement with an earlier published work.
文摘The objective of the present study is to investigate the effect of flow parameters on the free convection and mass transfer of an unsteady magnetohydrodynamic flow of an electrically conducting, viscous, and incompressible fluid past an infinite vertical porous plate under oscillatory suction velocity and thermal radiation. The Dufour (diffusion thermo) and Soret (thermal diffusion) effects are taken into account. The problem is solved numerically using the finite element method for the velocity, the temperature, and the concentration field. The expression for the skin friction, the rate of heat and mass transfer is obtained. The results are presented numerically through graphs and tables for the externally cooled plate (Gr 〉 0) and the externally heated plate (Gr 〈 0) to observe the effects of various parameters encountered in the equations.
文摘In this work, the Micropolar fluid flow and heat and mass transfer past a horizontal nonlinear stretching sheet through porous medium is studied including the Soret-Dufour effect in the presence of suction. A uniform magnetic field is applied transversely to the direction of the flow. The governing differential equations of the problem have been transformed into a system of non-dimensional differential equations which are solved numerically by Nachtsheim-Swigert iteration technique along with the sixth order Runge-Kutta integration scheme. The velocity, microrotation, temperature and concentration profiles are presented for different parameters. The present problem finds significant applications in hydromagnetic control of conducting polymeric sheets, magnetic materials processing, etc.
文摘An analysis of two-dimensional steady magneto-hydrodynamic free convection flow of an electrically conducting, viscous, incompressible fluid past an inclined stretching porous plate in the presence of a uniform magnetic field and thermal radiation with heat generation is made. Both the Dufour and Soret effects are considered for a hydrogen-air mixture as the non-chemically reacting fluid pair. The equations governing the flow, temperature and concentration fields are reduced to a system of joined non-linear ordinary differential equations by similarity transformation. Non-linear differential equations are integrated numerically by using Nachtsheim-Swigert shooting iteration technique along with sixth order Runge-Kutta integration scheme. Finally the significance of physical parameters which are of engineering interest are examined both in graphical and tabular form.
基金This research is supported by Department of Mathematics,Faculty of Science,Khon Kaen University,Fiscal Year 2022.
文摘This work aims to study the nonlinear ordinary differential equations(ODEs)system of magnetohydrodynamic(MHD)past over an inclined plate using Levenberg-Marquardt backpropagation neural networks(LMBNNs).The stochastic procedures LMBNNs are provided with three categories of sample statistics,testing,training,and verification.The nonlinear MHD system past over an inclined plate is divided into three profiles,dimensionless momentum,species(salinity),and energy(heat)conservations.The data is applied 15%,10%,and 75%for validation,testing,and training to solve the nonlinear system of MHD past over an inclined plate.A reference data set is designed to compare the obtained and proposed solutions for the MHD system.The plots of the absolute error(AE)are provided to check the accuracy and precision of the considered nonlinear system of MHD.The obtained numerical solutions of the nonlinear magnetohydrodynamic system have been considered to reduce the mean square error(MSE).For the capability,dependability,and aptitude of the stochastic LMBNNs procedure,the numerical performances are provided to authenticate the relative arrangements of MSE,error histograms(EHs),state transitions(STs),correlation,and regression.
文摘We made an elaborate scrutiny on the Soret and Joule effects of MHD mixed convective flow of an incompressible and electrically conducting viscous fluid past an infinite vertical porous plate taking Hall effects into account.Perturbation technique is used to solve the non-dimensional equations.The effects of the various non-dimensional parameters on velocity,temperature and concentration within the boundary layer are examined.Besides that,computational deliberations or discussions are also undertaken on the effects of the pertinent or significant parameters on the skin-friction coefficient and rates of heat and mass transfer in terms of the Nusselt and Sherwood numbers respectively.The concentration distribution increases with increase in Soret effect and decrease with increase in chemical reaction parameter.An increase in Prandtl number results to decrease the temperature distribution.Both the primary and secondary velocity components and temperature increases with increasing heat source parameter.Skin friction coefficient decreases with an increase in permeability parameter,whereas it shows reverse effect for thermal and mass Grashof numbers.Nusselt number increases with an increase in Prandtl number.Sherwood number reduces with increasing Soret number.
文摘This article inspects the effect of triple diffusion in a vertical conduit encapsulated with porous matrix and subjected to third kind boundary conditions.Third kind boundary condition is a combination of Dirichlet and Neumann boundary conditions which specifies a linear combination of function and its derivative values on the boundary.Homogeneous chemical reaction along with viscous and Darcy dissipation effects are included.Adapting the Boussinesq approximation,the soultal buoyancy effects due to concentration gradients of the dispersed components are taken into account.Applying suitable transformations,the conservation equations are reduced into dimensionless form and the dimensionless parameters evolved are thermal Grashof number (0≤Λ_(1)≤20),solutal Grashof number(for species 1 and 2,0≤Λ_(2);Λ_(3)≤20),porous (2≤σ≤8) and inertial parameters (0≤Ι≤6),Biot numbers(at the left and right walls,1≤Bi_(1);Bi_(2)≤10),Brinkman number (0≤Br≤1),Schmidt numbers (0≤Sc_(1);Sc_(2)≤6),Soret numbers (Sr_(1) =Sr_(2) =1) and temperature difference ratio (R_(T) = 1).Adopting perturbation technique,the analytical solutions which are applicable only when the Brinkman number is less than one is appraised.However for any values of the Brinkman number,Runge-Kutta shooting method is operated.The impact of selected parameters on the momentum,heat and dual species concentration fields are presented in the form of pictures.The solutions computed by numerical method are justified by comparing with the analytical method.The numerical and analytical solutions are equal in the absence of Darcy and viscous dissipations and the discrepancy advances as the Brinkman number expands.Further the solutions obtained are also justified by comparing the results with Zanchini[1]in the absence of chemical reaction for clear fluid.The thermal field is augmented with the Brinkman number for symmetric and asymmetric Biot numbers.However the profiles are highly distinct at the cold plate for unequal Biot numbers in comparison with equal Biot numbers.The conclusions are admissible to materials processing and chemical transport phenomena.
基金the Deanship of Scientific Research at King Khalid University,Abha,Saudi Arabia,for funding this work through the Research Group Project under Grant Number(RGP.2/144/42)funded by the Deanship of Scientific Research at Princess Nourah Bint Abdulrahman University through the Fast-track Research Funding Program。
文摘The magnetic impacts upon the transport of heat and mass of an electrically conducting nanofluid within an annulus among an inner rhombus with convex and outer cavity with periodic temperature/concentration profiles on its left wall are assessed by the ISPH method.The right wall has Tcand C,cflat walls are adiabatic,and the temperature and concentration of the left wall are altered sinusoidally with time.The features of the heat and mass transfer and fluid flow through an annulus are assessed across a wide scale of Hartmann number Ha,Soret number Sr,oscillation amplitude A,Dufour number Du,nanoparticles parameterΦ,oscillation frequency f,Rayleigh number Ra,and radius of a superellipse a at Lewis number Le=20,magnetic field’s angle g=45°,Prandtl number Pr=6.2,a superellipse coefficient n=3/2,and buoyancy parameter N=1.The results reveal that the velocity’s maximum reduces by 70.93%as Ha boosts from 0 to 50,and by 66.24%as coefficient a boosts from 0.1 to 0.4.Whilst the velocity’s maximum augments by 83.04%as Sr increases from 0.6 to 2 plus a decrease in Du from 1 to0.03.The oscillation amplitude A,and frequency f are significantly affecting the nanofluid speed,and heat and mass transfer inside an annulus.Increasing the parameters A and f is augmenting the values of mean Nusselt number-(Sh)and mean Sherwood number^-(Nu).Increasing the radius of a superellipse a enhances the values of^(Nu)and^(Sh).