The main objective of this work is to investigate analytically the steady nanofluid flow and heat transfer characteristics between nonparallel plane walls. Using appropriate transformations for the velocity and temper...The main objective of this work is to investigate analytically the steady nanofluid flow and heat transfer characteristics between nonparallel plane walls. Using appropriate transformations for the velocity and temperature, the basic nonlinear partial differential equations are reduced to the ordinary differential equations. Then, these equations have been solved analytically and numerically for some values of the governing parameters, Reynolds number, Re, channel half angle, α, Prandtl number, Pr, and Eckert number, Ec, using Adomian decomposition method and the Runge-Kutta method with mathematic package. Analytical and numerical results are searched for the skin friction coefficient, Nusselt number and the velocity and temperature profiles. It is found on one hand that the Nusselt number increases as Eckert number or channel half-angle increases, but it decreases as Reynolds number increases. On the other hand, it is also found that the presence of Cu nanoparticles in a water base fluid enhances heat transfer between nonparallel plane walls and in consequence the Nusselt number increases with the increase of nanoparticles volume fraction. Finally, an excellent agreement between analytical results and those obtained by numerical Runge-Kutta method is highly noticed.展开更多
In this study, the laminar heat transfer and nanofluid flow between two porous horizontal concentric cylinders was investigated. The problem is investigated in two different geometries and the Re=10, 25, 50, 75, 100 a...In this study, the laminar heat transfer and nanofluid flow between two porous horizontal concentric cylinders was investigated. The problem is investigated in two different geometries and the Re=10, 25, 50, 75, 100 and volume fraction 0, 0.2%, 0.5%, 2% and 5% that related to copper nanoparticles, and porous medium porosity of 0.5 and 0.9. Compared to the first geometry, the convective coefficient in the second geometry increases by 8.3%, 7% and 5.5% at Reynolds numbers of 100, 75 and 50, respectively. Comparison of the outlet temperatures for two heat fluxes of 300 and 1200 W/m^2 indicates a 2.5% temperature growth by a fourfold increase in the heat fluxes. Also, the higher Nusselt number is associated with the second geometry occurring at porosities of 0.9 and 0.5, respectively. In both geometries, the Nusselt number values at the porosity of 0.9 are higher, which is due to the increased nanofluid convection at higher porosities. The velocity of the nanofluid experiences a two-fold increase at the outlet compared to its inlet velocity in the first geometry and for both porosities. Similarly, a three-fold increase was achieved in the second geometry and for both porosities.展开更多
The main goal of this paper is to investigate natural convective heat transfer and flow characteristics of non-Newtonian nanofluid streaming between two infinite vertical flat plates in the presence of magnetic field ...The main goal of this paper is to investigate natural convective heat transfer and flow characteristics of non-Newtonian nanofluid streaming between two infinite vertical flat plates in the presence of magnetic field and thermal radiation.Initially,a similarity transformation is used to convert momentum and energy conservation equations in partial differential forms into non-linear ordinary differential equations (ODE) applying meaningful boundary conditions.In order to obtain the non-linear ODEs analytically,Galerkin method (GM) is employed.Subsequently,the ODEs are also solved by a reliable numerical solution.In order to test the accuracy,precision and reliability of the analytical method,results of the analytical analysis are compared with the numerical results.With respect to the comparisons,fairly good compatibilities with insignificant errors are observed.Eventually,the impacts of effective parameters including magnetic and radiation parameters and nanofluid volume fraction on the velocity,skin friction coefficient and Nusselt number distributions are comprehensively described.Based on the results,it is revealed that with increasing the role of magnetic force,velocity profile,skin friction coefficient and thermal performance descend.Radiation parameter has insignificant influence on velocity profile while it obviously has augmentative and decreasing effects on skin friction and Nusselt number,respectively.展开更多
The current investigation aims to explore the combined effects of heat and mass transfer on free convection of Sodium alginate-Fe_(3)O_(4) based Brinkmann type nanofluid flow over a vertical rotating frame.The Tiwari ...The current investigation aims to explore the combined effects of heat and mass transfer on free convection of Sodium alginate-Fe_(3)O_(4) based Brinkmann type nanofluid flow over a vertical rotating frame.The Tiwari and Das nanofluid model is employed to examine the effects of dimensionless numbers,including Grashof,Eckert,and Schmidt numbers and governing parameters like solid volume fraction of nanoparticles,Hall current,magnetic field,viscous dissipation,and the chemical reaction on the physical quantities.The dimensionless nonlinear partial differential equations are solved using a finite difference method known as Runge-Kutta Fehlberg(RKF-45)method.The variation of dimensionless velocity,temperature,concentration,skin friction,heat,and mass transfer rate,as well as for entropy generation and Bejan number with governing parameters,are presented graphically and are provided in tabular form.The results reveal that the Nusselt number increases with an increase in the solid volume fraction of nanoparticles.Furthermore,the rate of entropy generation and Bejan number depends upon the magnetic field and the Eckert number.展开更多
The present study is carried out to see the thermal-diffusion(Dufour) and diffusion-thermo(Soret) effects on the mixed convection boundary layer flow of viscoelastic nanofluid flow over a vertical stretching surface i...The present study is carried out to see the thermal-diffusion(Dufour) and diffusion-thermo(Soret) effects on the mixed convection boundary layer flow of viscoelastic nanofluid flow over a vertical stretching surface in a porous medium. Optimal homotopy analysis method(OHAM) is best candidate to handle highly nonlinear system of differential equations obtained from boundary layer partial differential equations via appropriate transformations. Graphical illustrations depicting different physical arising parameters against velocity, temperature and concentration distributions with required discussion have also been added. Numerically calculated values of skin friction coefficient, local Nusselt and Sherwood numbers are given in the form of table and well argued. It is found that nanofluid velocity increases with increase in mixed convective and viscoelastic parameters but it decreases with the increasing values of porosity parameter. Also, it is observed that Dufour number has opposite behavior on temperature and concentration profiles.展开更多
This study discusses the magnetohydrodynamic nanofluid flow over an inclined permeable surface influenced by mixed convection, and Cattaeo-Christov heat flux. The heat transfer analysis is performed in the presence of...This study discusses the magnetohydrodynamic nanofluid flow over an inclined permeable surface influenced by mixed convection, and Cattaeo-Christov heat flux. The heat transfer analysis is performed in the presence of a heat source/sink and thermal stratification. To gauge the energy loss during the process, an irreversibility analysis is also performed. A numerical solution to the envisaged problem is obtained using the bvp4c package of MATLAB. Graphs are drawn to assess the consequences of the arising parameters against the associated profiles. The results show that an augmentation in the magnetic field and nanomaterial volume fraction results in an enhancement in the temperature profile. A strong magnetic field can significantly reduce the fluid velocity. The behavior of the Skin friction coefficient against the different estimates of emerging parameters is discussed. .展开更多
The present study examines the thermal distribution of ternary nanofluid flow amid two spinning disks influenced by electric and magnetic fields. Keeping in view the shape of the particles, the electrically conducting...The present study examines the thermal distribution of ternary nanofluid flow amid two spinning disks influenced by electric and magnetic fields. Keeping in view the shape of the particles, the electrically conducting ternary nanofluid is analyzed with variable thermophysical features. Three types of nanoparticles namely Copper, Aluminum Oxide, and Graphene with spherical, cylindrical, and platelet shapes are taken respectively and are immersed in a (50-50)% ratio of water and ethylene glycol mixture which acts as a base fluid. The anticipated problem is addressed by employing a reliable and user-friendly numerical bvp4c built-in collocation scheme. This solution is then showcased through illustrations and tables. Strengthening the radiation results in an enhanced heat transfer rate. Radial and azimuthal velocities once rotation of disks is enhanced. The key findings provide a strong theoretical background in photovoltaic cells, solar collectors, radiators, solar water heaters, and many other applications.展开更多
The unsteady laminar magnetohydrodynamics (MHD) boundary layer flow and heat transfer of nanofluids over an accelerating convectively heated stretching sheet are numerically studied in the presence of a transverse m...The unsteady laminar magnetohydrodynamics (MHD) boundary layer flow and heat transfer of nanofluids over an accelerating convectively heated stretching sheet are numerically studied in the presence of a transverse magnetic field with heat source/sink The unsteady governing equations are solved by a shooting method with the Runge-Kutta- Fehlberg scheme. Three different types of water based nanofluids, containing copper, aluminium oxide, and titanium dioxide, are taken into consideration. The effects of the pertinent parameters on the fluid velocity, the temperature, the entropy generation num- ber, the Bejan number, the shear stress, and the heat transfer rate at the sheet surface are graphically and quantitatively discussed in detail. A comparison of the entropy generation due to the heat transfer and the fluid friction is made with the help of the Bejan number. It is observed that the presence of the metallic nanoparticles creates more entropy in the nanofluid flow than in the regular fluid flow.展开更多
This article examines a mathematical model to analyze the rotating flow of three-dimensional water based nanofluid over a convectively heated exponentially stretching sheet in the presence of transverse magnetic field...This article examines a mathematical model to analyze the rotating flow of three-dimensional water based nanofluid over a convectively heated exponentially stretching sheet in the presence of transverse magnetic field with additional effects of thermal radiation,Joule heating and viscous dissipation.Silver(Ag),copper(Cu),copper oxide(Cu O),aluminum oxide(Al_2O_3)and titanium dioxide(Ti O_2)have been taken under consideration as the nanoparticles and water(H_2O)as the base fluid.Using suitable similarity transformations,the governing partial differential equations(PDEs)of the modeled problem are transformed to the ordinary differential equations(ODEs).These ODEs are then solved numerically by applying the shooting method.For the particular situation,the results are compared with the available literature.The effects of different nanoparticles on the temperature distribution are also discussed graphically and numerically.It is witnessed that the skin friction coefficient is maximum for silver based nanofluid.Also,the velocity profile is found to diminish for the increasing values of the magnetic parameter.展开更多
The present study deals with the analysis of heat transfer of the unsteady Maxwell nanofluid flow in a squeezed rotating channel of a porous extensile surface subject to the velocity and thermal slip effects incorpora...The present study deals with the analysis of heat transfer of the unsteady Maxwell nanofluid flow in a squeezed rotating channel of a porous extensile surface subject to the velocity and thermal slip effects incorporating the theory of heat flow intensity of Cattaneo-Christov model for the expression of the energy distribution in preference to the classical Fourier’s law. A set of transformations is occupied to renovate the current model in a system of nonlinear ordinary differential equations that are numerically decoded with the help of MATLAB integrated function bvp4c. The effects of various flow control parameters are investigated for the momentum, temperature and diffusion profiles, as well as for the wall shearing stress and the heat and mass transfer. The results are finally described from the material point of view. A comparison of heat flux models of Cattaneo-Christov and Fourier is also performed. An important result from the present work is that the squeezing parameter is strong enough in the middle of the channel to retard the fluid flow.展开更多
In this study, Hydromagnetic Squeezing Nanofluid flow between two vertical plates in presence of a chemical reaction has been investigated. The governing equations were transformed by similarity transformation and the...In this study, Hydromagnetic Squeezing Nanofluid flow between two vertical plates in presence of a chemical reaction has been investigated. The governing equations were transformed by similarity transformation and the resulting ordinary differential equations were solved by collocation method. The velocity, temperature, concentration and magnetic induction profiles were determined with help of various flow parameters. The numerical scheme was simulated with aid of MATLAB. The results showed that increasing the squeeze number only boosts velocity and concentration while lowering temperature. Conversely, increasing the Hartmann number, Reynold’s magnetic number, Eckert number and Thermal Grashof number generally increases temperature but decreases both velocity and concentration. Chemical reaction rate and Soret number solely elevate concentration while Schmidt number only reduces it. The results of this study will be useful in the fields of oil and gas industry, plastic processing industries, filtration, food processing, lubrication system in machinery, Microfluidics devices for drug delivery and other related fields of nanotechnology.展开更多
The present study investigates the dynamic behavior of a ternary-hybrid nanofluid within a tapered asymmetric channel,focusing on the impact of unsteady oscillatory flow under the influence of a magnetic field.This st...The present study investigates the dynamic behavior of a ternary-hybrid nanofluid within a tapered asymmetric channel,focusing on the impact of unsteady oscillatory flow under the influence of a magnetic field.This study addresses temperature-sensitive water transport mechanisms relevant to industrial applications such as thermal management and energy-efficient fluid transport.By suspending nanoparticles of diverse shapes-platelets,blades,and spheres in a hybrid base fluid comprising cobalt ferrite,magnesium oxide,and graphene oxide,the study examines the influence of both small and large volume fraction values.The governing equations are converted into a dimensionless form.With suitable assumptions,the partial differential equations(PDEs)are simplified into ordinary differential equations(ODEs),which are then solved using an analyticalmethod.Theproposed solution is verified using a numerical approach with the BVP4C solver.The analysis yields detailed graphs that depict the behavior of key fluid flow parameters,such as velocity,temperature,concentration,skin friction,Nusselt number,and Sherwood number,within the tapered asymmetric channel.展开更多
Purpose:In this study,the Levenberg-Marquardt algorithm combined with a backpropagated artificial neural network(LMS-BANN)is employed to investigate the steady,incompressible flow of a Boger nanofluid between two clos...Purpose:In this study,the Levenberg-Marquardt algorithm combined with a backpropagated artificial neural network(LMS-BANN)is employed to investigate the steady,incompressible flow of a Boger nanofluid between two closely spaced symmetrical cylinders(BFCC).The research compares the effects of single and hybrid nanoparticles on velocity,pressure,and thermal distribution.Methodology:To implement LMS-BANN,the system of partial differential equations(PDEs)governing fluid dynamics is converted into a system of ordinary differential equations(ODEs)using suitable transformations.The reference dataset for LMS-BANN is generated by numerically solving these ODEs with the BVP4C method i.e Boundary Value Problem,4th-order,collocation method.Key findings:The study examines how variations in physical parameters influence the velocity and temperature profiles,utilizing regression analysis,training processes,and mean square error(MSE)graphs to evaluate and validate LMS-BANN's performance.The accuracy of the BFCC solution approximation with LMS-BANN is assessed through validation,training,and testing phases.The LMS-BANN model reported a mean square error(MSE)as small as 1.3134E−10 and practically very accurate in the prediction of the flow of fluid.Also,regression values peaked at R=1,which displays the outstanding work of the model.展开更多
The main aim of this paper is to propose a kernel-based method for solving the problem of squeezing Cu–Water nanofluid flow between parallel disks.Our method is based on Gaussian Hilbert–Schmidt SVD(HS-SVD),which gi...The main aim of this paper is to propose a kernel-based method for solving the problem of squeezing Cu–Water nanofluid flow between parallel disks.Our method is based on Gaussian Hilbert–Schmidt SVD(HS-SVD),which gives an alternate basis for the data-dependent subspace of“native”Hilbert space without ever forming kernel matrix.The well-conditioning linear system is one of the critical advantages of using the alternate basis obtained from HS-SVD.Numerical simulations are performed to illustrate the efficiency and applicability of the proposed method in the sense of accuracy.Numerical results obtained by the proposed method are assessed by comparing available results in references.The results demonstrate that the proposed method can be recommended as a good option to study the squeezing nanofluid flow in engineering problems.展开更多
This study focuses on numerically investigating thermal behavior within a differentially heated cavity filled with nanofluid with and without obstacles.Numerical comparison with previous studies proves the consistency...This study focuses on numerically investigating thermal behavior within a differentially heated cavity filled with nanofluid with and without obstacles.Numerical comparison with previous studies proves the consistency and efficacy of the lattice Boltzmann method associated with a single relaxation time and its possibility of studying the nanofluid and heat transfer with high accuracy.Key parameters,including nanoparticle type and concentration,Rayleigh number,fluid basis,and obstacle position and dimension,were examined to identify optimal conditions for enhancing heat transfer quality.Principal findings indicated that increasing the Rayleigh number boosts buoyancy forces and alters vortex structure,improving the heat transfer efficiency across all nanofluid configu-rations.Moreover,nanoparticles with higher thermal conductivity,particularly Cu nanoparticles,exhibit slight improvements in heat transfer quality compared to Al2O3 nanoparticles,while higher nanoparticle concentrations generally lead to enhanced heat transfer effectiveness.Water-Cu nanofluids also demonstrate superior heat transfer performance over ethylene glycol-Cu nanofluids.Furthermore,the presence of obstacles at cavity extremities hampers overall heat transfer,whereas those positioned centrally augment heat exchange rates.This research offers valuable insights into optimizing convective heat transfer in nanofluid-filled cavities crucial for various engineering applications.展开更多
Mixed convection flow of magnetohydrodynamic(MHD) Jeffrey nanofluid over a radially stretching surface with radiative surface is studied. Radial sheet is considered to be convectively heated. Convective boundary condi...Mixed convection flow of magnetohydrodynamic(MHD) Jeffrey nanofluid over a radially stretching surface with radiative surface is studied. Radial sheet is considered to be convectively heated. Convective boundary conditions through heat and mass are employed. The governing boundary layer equations are transformed into ordinary differential equations. Convergent series solutions of the resulting problems are derived. Emphasis has been focused on studying the effects of mixed convection, thermal radiation, magnetic field and nanoparticles on the velocity, temperature and concentration fields. Numerical values of the physical parameters involved in the problem are computed for the local Nusselt and Sherwood numbers are computed.展开更多
This paper describes the theoretical analysis for peristaltic motion of water base nanoBuid containing distinct types of the nanoparticles like Cu,TiO_2,and Al_2O_3.Equations of nano Quid are modelled and simplified b...This paper describes the theoretical analysis for peristaltic motion of water base nanoBuid containing distinct types of the nanoparticles like Cu,TiO_2,and Al_2O_3.Equations of nano Quid are modelled and simplified by constructing the suppositions of low Reynolds number as well as long wave length.The reduced equations are solved exactly.Solutions are represented through graphs.Outcomes for the velocity,temperature,pressure rise and stream lines are analyzed graphically.The work presented here is based on the fictitious values,however some other values can be tested experimentally.展开更多
Unsteady turbulent magnetohydrodynamic nanofluid hydrothermal treatment is studied. The zero- equation turbulence model is used to simulate turbulent flow. The modeling results obtained by applying the hybrid differen...Unsteady turbulent magnetohydrodynamic nanofluid hydrothermal treatment is studied. The zero- equation turbulence model is used to simulate turbulent flow. The modeling results obtained by applying the hybrid differential transformation method-finite difference method to solve this problem confirm its viability. An analytical procedure is used for finding the effects of the problem parameters. Results indicate that the average Nusselt number over the lower plate depends linearly on volume fraction of nanofluid, Hall parameter, turbulent Eckert number, and Reynolds number whereas it is inversely proportional on the Hartmann number and the turbulent parameter.展开更多
This study investigates the effect of injecting nanofluids containing nano-SiO_2 as drag reducing agents(DRA) at different concentrations on the pressure drop of air-water flow through horizontal pipe.The test fluid u...This study investigates the effect of injecting nanofluids containing nano-SiO_2 as drag reducing agents(DRA) at different concentrations on the pressure drop of air-water flow through horizontal pipe.The test fluid used in this study was air-water with nano-SiO_2 particles at 0.1%-1%mass concentration.The test sections of the experimental set-up were five pipes of the same length of 9 m with ID from 0.0127m-0.03175m(0.5 to 1.25 in).Airwater flow was run in slug flow regime under different volumetric flow rates.The results of drag reduction(η%)indicated that the addition of DRA could be efficient up to some dosage.Drag reduction performed much better for smaller pipe diameters than it did for larger ones.For various nanosilica concentrations,the maximum drag reduction was about 66.8%for 0.75%mass concentration of nanosilica.展开更多
Laminar two-dimensional unsteady mixed-convection boundary-layer flow of a viscous incompressible fluid past asymmetric wedge with variable surface temperature embedded in a porous medium saturated with a nanofluid ha...Laminar two-dimensional unsteady mixed-convection boundary-layer flow of a viscous incompressible fluid past asymmetric wedge with variable surface temperature embedded in a porous medium saturated with a nanofluid has been studied. The employed mathematical model for the nanofluid takes into account the effects of Brownian motion and thermophoresis. The velocity in the potential flow is assumed to vary arbitrary with time. The non-Darcy effects including convective, boundary and inertial effects will be included in the analysis. The unsteadiness is due to the time-dependent free stream velocity. The governing boundary layer equations along with the boundary conditions are converted into dimensionless form by a non-similar transformation, and then resulting system of coupled non-linear partial differential equations are solved by perturbation solutions for small dimensionless time until the second order. Numerical solutions of the governing equations are obtained employing the implicit finite-difference scheme in combination with the quasi-linearization technique. To validating the method used, we compared our results with previous results in earlier papers on special cases of the problem and are found to be in agreement. Effects of various parameters on velocity, temperature and nanoparticle volume fraction profiles are graphically presented.展开更多
文摘The main objective of this work is to investigate analytically the steady nanofluid flow and heat transfer characteristics between nonparallel plane walls. Using appropriate transformations for the velocity and temperature, the basic nonlinear partial differential equations are reduced to the ordinary differential equations. Then, these equations have been solved analytically and numerically for some values of the governing parameters, Reynolds number, Re, channel half angle, α, Prandtl number, Pr, and Eckert number, Ec, using Adomian decomposition method and the Runge-Kutta method with mathematic package. Analytical and numerical results are searched for the skin friction coefficient, Nusselt number and the velocity and temperature profiles. It is found on one hand that the Nusselt number increases as Eckert number or channel half-angle increases, but it decreases as Reynolds number increases. On the other hand, it is also found that the presence of Cu nanoparticles in a water base fluid enhances heat transfer between nonparallel plane walls and in consequence the Nusselt number increases with the increase of nanoparticles volume fraction. Finally, an excellent agreement between analytical results and those obtained by numerical Runge-Kutta method is highly noticed.
文摘In this study, the laminar heat transfer and nanofluid flow between two porous horizontal concentric cylinders was investigated. The problem is investigated in two different geometries and the Re=10, 25, 50, 75, 100 and volume fraction 0, 0.2%, 0.5%, 2% and 5% that related to copper nanoparticles, and porous medium porosity of 0.5 and 0.9. Compared to the first geometry, the convective coefficient in the second geometry increases by 8.3%, 7% and 5.5% at Reynolds numbers of 100, 75 and 50, respectively. Comparison of the outlet temperatures for two heat fluxes of 300 and 1200 W/m^2 indicates a 2.5% temperature growth by a fourfold increase in the heat fluxes. Also, the higher Nusselt number is associated with the second geometry occurring at porosities of 0.9 and 0.5, respectively. In both geometries, the Nusselt number values at the porosity of 0.9 are higher, which is due to the increased nanofluid convection at higher porosities. The velocity of the nanofluid experiences a two-fold increase at the outlet compared to its inlet velocity in the first geometry and for both porosities. Similarly, a three-fold increase was achieved in the second geometry and for both porosities.
文摘The main goal of this paper is to investigate natural convective heat transfer and flow characteristics of non-Newtonian nanofluid streaming between two infinite vertical flat plates in the presence of magnetic field and thermal radiation.Initially,a similarity transformation is used to convert momentum and energy conservation equations in partial differential forms into non-linear ordinary differential equations (ODE) applying meaningful boundary conditions.In order to obtain the non-linear ODEs analytically,Galerkin method (GM) is employed.Subsequently,the ODEs are also solved by a reliable numerical solution.In order to test the accuracy,precision and reliability of the analytical method,results of the analytical analysis are compared with the numerical results.With respect to the comparisons,fairly good compatibilities with insignificant errors are observed.Eventually,the impacts of effective parameters including magnetic and radiation parameters and nanofluid volume fraction on the velocity,skin friction coefficient and Nusselt number distributions are comprehensively described.Based on the results,it is revealed that with increasing the role of magnetic force,velocity profile,skin friction coefficient and thermal performance descend.Radiation parameter has insignificant influence on velocity profile while it obviously has augmentative and decreasing effects on skin friction and Nusselt number,respectively.
文摘The current investigation aims to explore the combined effects of heat and mass transfer on free convection of Sodium alginate-Fe_(3)O_(4) based Brinkmann type nanofluid flow over a vertical rotating frame.The Tiwari and Das nanofluid model is employed to examine the effects of dimensionless numbers,including Grashof,Eckert,and Schmidt numbers and governing parameters like solid volume fraction of nanoparticles,Hall current,magnetic field,viscous dissipation,and the chemical reaction on the physical quantities.The dimensionless nonlinear partial differential equations are solved using a finite difference method known as Runge-Kutta Fehlberg(RKF-45)method.The variation of dimensionless velocity,temperature,concentration,skin friction,heat,and mass transfer rate,as well as for entropy generation and Bejan number with governing parameters,are presented graphically and are provided in tabular form.The results reveal that the Nusselt number increases with an increase in the solid volume fraction of nanoparticles.Furthermore,the rate of entropy generation and Bejan number depends upon the magnetic field and the Eckert number.
文摘The present study is carried out to see the thermal-diffusion(Dufour) and diffusion-thermo(Soret) effects on the mixed convection boundary layer flow of viscoelastic nanofluid flow over a vertical stretching surface in a porous medium. Optimal homotopy analysis method(OHAM) is best candidate to handle highly nonlinear system of differential equations obtained from boundary layer partial differential equations via appropriate transformations. Graphical illustrations depicting different physical arising parameters against velocity, temperature and concentration distributions with required discussion have also been added. Numerically calculated values of skin friction coefficient, local Nusselt and Sherwood numbers are given in the form of table and well argued. It is found that nanofluid velocity increases with increase in mixed convective and viscoelastic parameters but it decreases with the increasing values of porosity parameter. Also, it is observed that Dufour number has opposite behavior on temperature and concentration profiles.
文摘This study discusses the magnetohydrodynamic nanofluid flow over an inclined permeable surface influenced by mixed convection, and Cattaeo-Christov heat flux. The heat transfer analysis is performed in the presence of a heat source/sink and thermal stratification. To gauge the energy loss during the process, an irreversibility analysis is also performed. A numerical solution to the envisaged problem is obtained using the bvp4c package of MATLAB. Graphs are drawn to assess the consequences of the arising parameters against the associated profiles. The results show that an augmentation in the magnetic field and nanomaterial volume fraction results in an enhancement in the temperature profile. A strong magnetic field can significantly reduce the fluid velocity. The behavior of the Skin friction coefficient against the different estimates of emerging parameters is discussed. .
文摘The present study examines the thermal distribution of ternary nanofluid flow amid two spinning disks influenced by electric and magnetic fields. Keeping in view the shape of the particles, the electrically conducting ternary nanofluid is analyzed with variable thermophysical features. Three types of nanoparticles namely Copper, Aluminum Oxide, and Graphene with spherical, cylindrical, and platelet shapes are taken respectively and are immersed in a (50-50)% ratio of water and ethylene glycol mixture which acts as a base fluid. The anticipated problem is addressed by employing a reliable and user-friendly numerical bvp4c built-in collocation scheme. This solution is then showcased through illustrations and tables. Strengthening the radiation results in an enhanced heat transfer rate. Radial and azimuthal velocities once rotation of disks is enhanced. The key findings provide a strong theoretical background in photovoltaic cells, solar collectors, radiators, solar water heaters, and many other applications.
文摘The unsteady laminar magnetohydrodynamics (MHD) boundary layer flow and heat transfer of nanofluids over an accelerating convectively heated stretching sheet are numerically studied in the presence of a transverse magnetic field with heat source/sink The unsteady governing equations are solved by a shooting method with the Runge-Kutta- Fehlberg scheme. Three different types of water based nanofluids, containing copper, aluminium oxide, and titanium dioxide, are taken into consideration. The effects of the pertinent parameters on the fluid velocity, the temperature, the entropy generation num- ber, the Bejan number, the shear stress, and the heat transfer rate at the sheet surface are graphically and quantitatively discussed in detail. A comparison of the entropy generation due to the heat transfer and the fluid friction is made with the help of the Bejan number. It is observed that the presence of the metallic nanoparticles creates more entropy in the nanofluid flow than in the regular fluid flow.
文摘This article examines a mathematical model to analyze the rotating flow of three-dimensional water based nanofluid over a convectively heated exponentially stretching sheet in the presence of transverse magnetic field with additional effects of thermal radiation,Joule heating and viscous dissipation.Silver(Ag),copper(Cu),copper oxide(Cu O),aluminum oxide(Al_2O_3)and titanium dioxide(Ti O_2)have been taken under consideration as the nanoparticles and water(H_2O)as the base fluid.Using suitable similarity transformations,the governing partial differential equations(PDEs)of the modeled problem are transformed to the ordinary differential equations(ODEs).These ODEs are then solved numerically by applying the shooting method.For the particular situation,the results are compared with the available literature.The effects of different nanoparticles on the temperature distribution are also discussed graphically and numerically.It is witnessed that the skin friction coefficient is maximum for silver based nanofluid.Also,the velocity profile is found to diminish for the increasing values of the magnetic parameter.
文摘The present study deals with the analysis of heat transfer of the unsteady Maxwell nanofluid flow in a squeezed rotating channel of a porous extensile surface subject to the velocity and thermal slip effects incorporating the theory of heat flow intensity of Cattaneo-Christov model for the expression of the energy distribution in preference to the classical Fourier’s law. A set of transformations is occupied to renovate the current model in a system of nonlinear ordinary differential equations that are numerically decoded with the help of MATLAB integrated function bvp4c. The effects of various flow control parameters are investigated for the momentum, temperature and diffusion profiles, as well as for the wall shearing stress and the heat and mass transfer. The results are finally described from the material point of view. A comparison of heat flux models of Cattaneo-Christov and Fourier is also performed. An important result from the present work is that the squeezing parameter is strong enough in the middle of the channel to retard the fluid flow.
文摘In this study, Hydromagnetic Squeezing Nanofluid flow between two vertical plates in presence of a chemical reaction has been investigated. The governing equations were transformed by similarity transformation and the resulting ordinary differential equations were solved by collocation method. The velocity, temperature, concentration and magnetic induction profiles were determined with help of various flow parameters. The numerical scheme was simulated with aid of MATLAB. The results showed that increasing the squeeze number only boosts velocity and concentration while lowering temperature. Conversely, increasing the Hartmann number, Reynold’s magnetic number, Eckert number and Thermal Grashof number generally increases temperature but decreases both velocity and concentration. Chemical reaction rate and Soret number solely elevate concentration while Schmidt number only reduces it. The results of this study will be useful in the fields of oil and gas industry, plastic processing industries, filtration, food processing, lubrication system in machinery, Microfluidics devices for drug delivery and other related fields of nanotechnology.
基金supported by the Government of the Basque Country,programs:Elkartek Grant No.DBaskIN ELKARTEK 25/28 and Grant No.:KK-2024/00035 and ITSAS-REM Grant No.:IT1514-22 funded by the High-Level Talent Research Start-up Project Funding of Henan Academy of Sciences(Project No.241819246).
文摘The present study investigates the dynamic behavior of a ternary-hybrid nanofluid within a tapered asymmetric channel,focusing on the impact of unsteady oscillatory flow under the influence of a magnetic field.This study addresses temperature-sensitive water transport mechanisms relevant to industrial applications such as thermal management and energy-efficient fluid transport.By suspending nanoparticles of diverse shapes-platelets,blades,and spheres in a hybrid base fluid comprising cobalt ferrite,magnesium oxide,and graphene oxide,the study examines the influence of both small and large volume fraction values.The governing equations are converted into a dimensionless form.With suitable assumptions,the partial differential equations(PDEs)are simplified into ordinary differential equations(ODEs),which are then solved using an analyticalmethod.Theproposed solution is verified using a numerical approach with the BVP4C solver.The analysis yields detailed graphs that depict the behavior of key fluid flow parameters,such as velocity,temperature,concentration,skin friction,Nusselt number,and Sherwood number,within the tapered asymmetric channel.
基金Deanship of Research and Graduate Studies at King Khalid University,KSA for funding this work through Large Research Project under grant number RGP.2/30/46.
文摘Purpose:In this study,the Levenberg-Marquardt algorithm combined with a backpropagated artificial neural network(LMS-BANN)is employed to investigate the steady,incompressible flow of a Boger nanofluid between two closely spaced symmetrical cylinders(BFCC).The research compares the effects of single and hybrid nanoparticles on velocity,pressure,and thermal distribution.Methodology:To implement LMS-BANN,the system of partial differential equations(PDEs)governing fluid dynamics is converted into a system of ordinary differential equations(ODEs)using suitable transformations.The reference dataset for LMS-BANN is generated by numerically solving these ODEs with the BVP4C method i.e Boundary Value Problem,4th-order,collocation method.Key findings:The study examines how variations in physical parameters influence the velocity and temperature profiles,utilizing regression analysis,training processes,and mean square error(MSE)graphs to evaluate and validate LMS-BANN's performance.The accuracy of the BFCC solution approximation with LMS-BANN is assessed through validation,training,and testing phases.The LMS-BANN model reported a mean square error(MSE)as small as 1.3134E−10 and practically very accurate in the prediction of the flow of fluid.Also,regression values peaked at R=1,which displays the outstanding work of the model.
文摘The main aim of this paper is to propose a kernel-based method for solving the problem of squeezing Cu–Water nanofluid flow between parallel disks.Our method is based on Gaussian Hilbert–Schmidt SVD(HS-SVD),which gives an alternate basis for the data-dependent subspace of“native”Hilbert space without ever forming kernel matrix.The well-conditioning linear system is one of the critical advantages of using the alternate basis obtained from HS-SVD.Numerical simulations are performed to illustrate the efficiency and applicability of the proposed method in the sense of accuracy.Numerical results obtained by the proposed method are assessed by comparing available results in references.The results demonstrate that the proposed method can be recommended as a good option to study the squeezing nanofluid flow in engineering problems.
文摘This study focuses on numerically investigating thermal behavior within a differentially heated cavity filled with nanofluid with and without obstacles.Numerical comparison with previous studies proves the consistency and efficacy of the lattice Boltzmann method associated with a single relaxation time and its possibility of studying the nanofluid and heat transfer with high accuracy.Key parameters,including nanoparticle type and concentration,Rayleigh number,fluid basis,and obstacle position and dimension,were examined to identify optimal conditions for enhancing heat transfer quality.Principal findings indicated that increasing the Rayleigh number boosts buoyancy forces and alters vortex structure,improving the heat transfer efficiency across all nanofluid configu-rations.Moreover,nanoparticles with higher thermal conductivity,particularly Cu nanoparticles,exhibit slight improvements in heat transfer quality compared to Al2O3 nanoparticles,while higher nanoparticle concentrations generally lead to enhanced heat transfer effectiveness.Water-Cu nanofluids also demonstrate superior heat transfer performance over ethylene glycol-Cu nanofluids.Furthermore,the presence of obstacles at cavity extremities hampers overall heat transfer,whereas those positioned centrally augment heat exchange rates.This research offers valuable insights into optimizing convective heat transfer in nanofluid-filled cavities crucial for various engineering applications.
文摘Mixed convection flow of magnetohydrodynamic(MHD) Jeffrey nanofluid over a radially stretching surface with radiative surface is studied. Radial sheet is considered to be convectively heated. Convective boundary conditions through heat and mass are employed. The governing boundary layer equations are transformed into ordinary differential equations. Convergent series solutions of the resulting problems are derived. Emphasis has been focused on studying the effects of mixed convection, thermal radiation, magnetic field and nanoparticles on the velocity, temperature and concentration fields. Numerical values of the physical parameters involved in the problem are computed for the local Nusselt and Sherwood numbers are computed.
文摘This paper describes the theoretical analysis for peristaltic motion of water base nanoBuid containing distinct types of the nanoparticles like Cu,TiO_2,and Al_2O_3.Equations of nano Quid are modelled and simplified by constructing the suppositions of low Reynolds number as well as long wave length.The reduced equations are solved exactly.Solutions are represented through graphs.Outcomes for the velocity,temperature,pressure rise and stream lines are analyzed graphically.The work presented here is based on the fictitious values,however some other values can be tested experimentally.
文摘Unsteady turbulent magnetohydrodynamic nanofluid hydrothermal treatment is studied. The zero- equation turbulence model is used to simulate turbulent flow. The modeling results obtained by applying the hybrid differential transformation method-finite difference method to solve this problem confirm its viability. An analytical procedure is used for finding the effects of the problem parameters. Results indicate that the average Nusselt number over the lower plate depends linearly on volume fraction of nanofluid, Hall parameter, turbulent Eckert number, and Reynolds number whereas it is inversely proportional on the Hartmann number and the turbulent parameter.
文摘This study investigates the effect of injecting nanofluids containing nano-SiO_2 as drag reducing agents(DRA) at different concentrations on the pressure drop of air-water flow through horizontal pipe.The test fluid used in this study was air-water with nano-SiO_2 particles at 0.1%-1%mass concentration.The test sections of the experimental set-up were five pipes of the same length of 9 m with ID from 0.0127m-0.03175m(0.5 to 1.25 in).Airwater flow was run in slug flow regime under different volumetric flow rates.The results of drag reduction(η%)indicated that the addition of DRA could be efficient up to some dosage.Drag reduction performed much better for smaller pipe diameters than it did for larger ones.For various nanosilica concentrations,the maximum drag reduction was about 66.8%for 0.75%mass concentration of nanosilica.
文摘Laminar two-dimensional unsteady mixed-convection boundary-layer flow of a viscous incompressible fluid past asymmetric wedge with variable surface temperature embedded in a porous medium saturated with a nanofluid has been studied. The employed mathematical model for the nanofluid takes into account the effects of Brownian motion and thermophoresis. The velocity in the potential flow is assumed to vary arbitrary with time. The non-Darcy effects including convective, boundary and inertial effects will be included in the analysis. The unsteadiness is due to the time-dependent free stream velocity. The governing boundary layer equations along with the boundary conditions are converted into dimensionless form by a non-similar transformation, and then resulting system of coupled non-linear partial differential equations are solved by perturbation solutions for small dimensionless time until the second order. Numerical solutions of the governing equations are obtained employing the implicit finite-difference scheme in combination with the quasi-linearization technique. To validating the method used, we compared our results with previous results in earlier papers on special cases of the problem and are found to be in agreement. Effects of various parameters on velocity, temperature and nanoparticle volume fraction profiles are graphically presented.