Free Convective Flow Of Nanofluid Research Articles

Analysis of free convective flow of nanofluid due to inclined surface with thermos-diffusion effects and chemical reaction

An unsteady free convective flow of nanofluid is studied due to inclined surface in presence of thermos-diffusion effects. The chemical reaction, radiative phenomenon and heat source features are also utilized to discuss the transport phenomenon. The properties of nanomaterials are endorsed with interaction of copper, titanium oxide and aluminum oxide nanoparticles. The dimensionless system is achieved for the governing model. The analysis solution with perturbation technique is suggested. The illustration of thermal flow problem is visualized with variation of parameters graphically. The numerical outcomes are also computed and illustrated.

Dual Stratification on the Double Diffusive Magnetohydrodynamics Flow of Nanofluids with Dissipation Effects-Revised Buongiorno Model

We analyze the effects of double stratification and dissipation on the hydro magnetic free convection flow of nanofluids over a vertical plate in this work. Considered two different kinds of nanofluids, such as copper and alumina–water nanofluids. By employing the similarity transformation, partial differential equations are converted into non-linear ordinary differential equations, which can be numerically computed with MATLAB. In practical situations where the heat and mass transfer mechanisms run simultaneously, the analysis of natural convection in the influence of double stratification is a fundamentally interesting and important problem, because of its broad range of engineering applications. These applications include the rejection of heat into the environment, such as lakes, rivers, and seas; the storage of thermal energy, such as solar ponds; and the transmission of heat from thermal sources, such as the condensers of power plants. To highlight the impact of double stratification and dissipation on the hydromagnetic free convective flow of nanofluid over a vertical plate, a wide variety of parameter values are used. The numerical outcomes for the different parameters of velocity, temperature, volume fraction, and concentration are obtained and displayed graphically. The skin friction coefficient and reduced Nusselt number are also determined numerically and tabulated.

A design of neuro-computational approach for double‐diffusive natural convection nanofluid flow

The artificial intelligence based neural networking with Back Propagated Levenberg-Marquardt method (NN-BPLMM) is developed to explore the modeling of double‐diffusive free convection nanofluid flow considering suction/injection, Brownian motion and thermophoresis effects past an inclined permeable sheet implanted in a porous medium. By applying suitable transformations, the PDEs presenting the proposed problem are transformed into ordinary ones. A reference dataset of NN-BPLMM is fabricated for multiple influential variants of the model representing scenarios by applying Lobatto III-A numerical technique. The reference data is trained through testing, training and validation operations to optimize and compare the approximated solution with desired (standard) results. The reliability, steadiness, capability and robustness of NN-BPLMM is authenticated through MSE based fitness curves, error through histograms, regression illustrations and absolute errors. The investigations suggest that the temperature enhances with the upsurge in thermophoresis impact during suction and decays for injection, whereas increasing Brownian effect decreases the temperature in the presence of wall suction and reverse behavior is seen for injection. The best measures of performance in form of mean square errors are attained as 7.1058×10−10,2.9262×10−10,1.1652×10−08,1.5657×10−10 and 5.5652×10−10 against 969, 824, 467, 277 and 650 iterations. The comparative study signifies the authenticity of proposed solver with the absolute errors about 10−7 to 10−3 for all influential parameters results.

Free convection nanofluid flow past a vertical isothermal cone surface in the presence of viscous dissipation and MHD with heat flux

Free convection nanofluid flow past a vertical isothermal cone surface in the presence of viscous dissipation and MHD with heat flux

Further analysis of double-diffusive flow of nanofluid through a porous medium situated on an inclined plane: AI-based Levenberg–Marquardt scheme with backpropagated neural network

The present article exploits a novel application of AI-based Levenberg–Marquardt scheme with backpropagated neural network (LMS–BPNN) to analyze the double-diffusive free convection nanofluid flow model (DDFC-NFM) over an inclined plate in the existence of Brownian motion and thermophoresis properties embedded in a porous medium. The governing PDEs representing DDFC-NFM are transformed into system of nonlinear ODEs by applying suitable transformation. The reference data set is generated from Lobatto III-A numerical solver by variation of magnetic field parameter (M), thermal Grashof number (Gr), angle of inclination (α), Brownian motion parameter (Nb), Dufour-solutal Lewis number (Ld), modified Dufour parameter (Nd) and thermophoresis parameter (Nt) for all scenarios of the designed LMS–BPNN. The approximate solution and its comparison with standard solution are analyzed by execution of training, testing and validation procedure of the designed LMS–BPNN. The effectiveness and reliable performance of LMS–BPNN are endorsed with MSE-based fitness curve, regression analysis, error histogram analysis and correlation index. Results reveal that velocity increases with the rise in Gr, whereas reverse trend has been noticed for angle of inclination and magnetic field parameter and the temperature profile increases with the increase in Nb, Nd and Nt. The solutal concentration profile increases with the increment in Ld, while an increase in Nd causes a decrease in it. When Nt increases, the enhancement in the nanoparticle volume frictions occurs, but an opposite behavior is depicted for Brownian motion parameter.

Mass transfer effect on viscous dissipative MHD flow of nanofluid over a stretching sheet embedded in a porous medium

Present analysis elucidates the steady free convective flow of nanofluid over a stretching sheet embedded in a porous medium. Mass transfer analysis with chemical reaction acts a great role in this study. The consideration of viscous dissipation makes the heat transfer analysis more interesting. The governing equations are remodelled as a system of ordinary differential equation adopting similarity transformation and treated numerically by 4th order Runge-Kutta method along with Shooting technique. The present results are compared with the earlier results which gives a good agreement. Some important findings are; porosity acts as aiding force whereas magnetic parameter as resistive force for fluid velocity, larger values of chemical reaction parameter result lower velocity and concentration. The study is relevant in polymer processing, food processing industries and chemical industries.

Passive control nanoparticles in double‐diffusive free convection nanofluid flow over an inclined permeable plate

AbstractThe present study has been conducted to acquire the solutions for the flow problem of an incompressible nanofluid past a permeable inclined plate implanted in a porous medium. In this study, double‐diffusivity, Brownian motion, and thermophoresis as well as passive control nanoparticles have been studied. We employ Lie group transformation on the ruling equations to extract nonlinear ordinary differential equations and solve them numerically using the fourth‐order Runge‐Kutta method and shooting approach. The supremacy of affined parameters on temperature and velocity distributions has been exposed by means of tables and graphs. This investigation suggests that both fluid velocity and nanoparticle concentration are enhanced by the modified Dufour parameter and the thermophoresis parameter. The assistance of the Lewis number intensifies the heat transport for suction.

The Effective of Nano Particles from Many Materials with the Free Convection Nanofluid Flow and Heat Transfer over Stretching Sheet with Heat Source

The Effective of Nano Particles from Many Materials with the Free Convection Nanofluid Flow and Heat Transfer over Stretching Sheet with Heat Source

MHD 3D free convective flow of nanofluid over an exponentially stretching sheet with chemical reaction

This paper deals with a problem where the effect of variable magnetic field and chemical reaction on free convective flow of an electrically conducting incompressible water based nanofluid over an exponentially stretching sheet has been investigated. In the present study, Buongiorno model associated with Brownian motion and thermophoretic diffusion is employed to describe the heat transfer enhancement of nanofluids. Some suitable similarity transformations reduced the governing boundary layer non-linear partial differential equations into a set of ordinary non-linear differential equations. The transformed equations are then solved numerically using fourth order Runga-Kutta method along with Shooting technique. The major outcomes of the present study is that the magnetic field impedes the fluid motion while thermal as well as mass buoyancy forces accelerate it, the thermophoretic diffusion enhances dimensionless fluid temperature as well as concentration leading to thicker thermal and concentration boundary layers. On the other hand, concentration exponent, Brownian motion parameter and chemical reaction parameter exhibit reverse trend on temperature and concentration. In addition, the presence of magnetic field under the influence of thermal as well as mass buoyancies supports to reduce the rate of heat transfer as well as wall shear stress while the first order chemical reaction develops a thinner concentration boundary layer.

3D free convective MHD flow of nanofluid over permeable linear stretching sheet with thermal radiation

This paper mainly focuses on the influence of transverse magnetic field as well as thermal radiation on three-dimensional free convective flow of nanofluid over a linear stretching sheet. One remarkable aspect of this study is that a new micro-convection model namely Patel model has been introduced in view of enhancement of thermal conductivity and hence more heat transfer capability of nanofluid. The non-linear partial differential equations have been converted into strong non-linear ordinary differential equations by employing suitable transformations and these transformed equations are solved by Runga-Kutta method of fourth order along with Shooting technique as well as Secant method for better approximation. From this study, it is found that the presence of magnetic field slows down the fluid motion while it enhances the fluid temperature leading to a reduction in heat transfer rate from the surface. It is also found that enhancing thermal radiation parameter causes a reduction in heat transfer rate.

Unsteady MHD Free Convection Flow of Nanofluid Past an Accelerated Vertical Plate with Variable Temperature and Thermal Radiation

An analytical study is performed to study the problem of nanofluid flow and heat transfer due to the exponentially accelerated motion of an infinite vertical plate in the presence of (i) magnetic field, (ii) thermal radiation and (iii) variable temperature at the plate. A range of nanofluids containing nanoparticles of aluminium oxide, copper, titanium oxide and silver with nanoparticle volume fraction range \(\le \)0.04 are considered. The partial differential equations governing the flow are solved by Laplace transform technique. Excellent validation of the present results is achieved with existing results in the literature. The effects of various parameters occurring into the problem such as nanoparticle volume fraction, nanofluid type, magnetic parameter, radiation parameter, accelerating parameter and thermal Grashof number on the velocity and temperature profiles, skin friction coefficient and Nusselt number are easily examined and discussed via the closed forms obtained which may be further used to verify the validity of obtained numerical solutions for more complicated transient free convection nanofluid flow problems.

Magnetic field analysis in a suspension of gyrotactic microorganisms and nanoparticles over a stretching surface

The combine effects of magnetic field bioconvection, Brownian motion and thermophoresis on a free convection nanofluid flow over a stretching sheet containing gyrotactic microorganisms are investigated. The self-similar Buongiorno model is analyzed first time for stretching sheet numerically. The present results are compared with available data and are found in an excellent agreement. Pertinent results are presented graphically and discussed quantitatively with respect to variation in bioconvection parameters.

Free convection nanofluid flow in the stagnation-point region of a three-dimensional body.

Analytical results are presented for a steady three-dimensional free convection flow in the stagnation point region over a general curved isothermal surface placed in a nanofluid. The momentum equations in x- and y-directions, energy balance equation, and nanoparticle concentration equation are reduced to a set of four fully coupled nonlinear differential equations under appropriate similarity transformations. The well known technique optimal homotopy analysis method (OHAM) is used to obtain the exact solution explicitly, whose convergence is then checked in detail. Besides, the effects of the physical parameters, such as the Lewis number, the Brownian motion parameter, the thermophoresis parameter, and the buoyancy ratio on the profiles of velocities, temperature, and concentration, are studied and discussed. Furthermore the local skin friction coefficients in x- and y-directions, the local Nusselt number, and the local Sherwood number are examined for various values of the physical parameters.

Numerical study of transient magnetohydrodynamic radiative free convection nanofluid flow from a stretching permeable surface

Transient mixed convective laminar boundary layer flow of an incompressible, viscous, dissipative, electrically conducting nanofluid from a continuously stretching permeable surface in the presence of magnetic field and thermal radiation flux is studied. The model used for the unsteadiness in the momentum, temperature, and concentration fields is based on the time-dependent stretching velocity and surface temperature and concentration. Similarity transformations are used to convert the governing time-dependent nonlinear boundary layer equations for momentum, thermal energy, and concentration to a system of nonlinear ordinary coupled differential equations with appropriate boundary conditions. The transformed model is shown to be controlled by a number of thermophysical parameters, namely the magnetic parameter, thermal convective parameter, mass convective parameter, suction parameter, radiation-conduction parameter, Eckert number, Prandtl number, Lewis number, Brownian motion parameter, thermophoresis parameter, and the unsteadiness parameter. Numerical solutions are obtained with the robust Nactsheim–Swigert shooting technique together with Runge–Kutta sixth-order iteration schemes. Comparisons with previously published work are performed and are found to be in excellent agreement. The effects of selected parameters on velocity, temperature, and concentration distributions and furthermore on skin friction coefficients, heat transfer rate (Nusselt number), and mass transfer rate (Sherwood number) are presented graphically. The current study has applications in high-temperature nano-technological materials processing.

Free convective flow of nanofluid having two nanoparticles inside a complicated cavity

In this paper, free convective flow and thermal behaviors of nanofluid inside a complicated enclosure is investigated. The cavity consists of a centered heated diamond shaped hollow obstacle. The vertical walls are constantly and uniformly less heated than the obstacle. The base surface of the cavity is insulated perfectly. The upper horizontal part of the enclosure is surrounded by solid material with constant thermal conductivity. The upper boundary of this solid region is considered as adiabatic. The working fluid is water based nanofluid having two nanoparticles alumina and copper. The integral forms of the governing equations are solved numerically using Galerkin’s Weighted Residual Finite Element method. Computational domains are divided into finite numbers of body fitted control volumes with collocated variable arrangement. Results are presented in the form of average Nusselt number (Nu), average temperature (θav), mean velocity of the nanofluid (Vav), mid height horizontal and vertical velocities for a selected range of convective parameter Rayleigh number Ra (103−106) and viscosity parameter Pr (4.2−8.8). Streamlines and isothermal lines are also displayed for the above mentioned parameters. The results indicate that the highest Nu is found for both greatest Ra and Pr.

Heat and mass transfer of unsteady natural convection flow of some nanofluids past a vertical infinite flat plate with radiation effect

This paper considers the heat and mass transfer characteristics of some nanofluid flows past a vertical infinite flat plate. The radiation effect for two distinct types of thermal boundary conditions is also taken into account. Derivation of exact analytical solutions are aimed for different water-based nanofluids containing Cu, Ag, CuO, Al2O3, and TiO2. The velocity and temperature profiles, skin friction coefficient and Nusselt number are easily examined and discussed via the closed forms obtained which may be further used to verify the validity of obtained numerical solutions for more complicated transient free convection nanofluid flow problems.