Increase In Thermophoresis Parameter Research Articles

Heat transmission in Darcy-Forchheimer flow of Sutterby nanofluid containing gyrotactic microorganisms

PurposeThis paper aims to deal with the heat transmission of Sutterby fluid-containing gyrotactic microorganism by incorporating non-Darcy resistance law. The mathematical modeling is based on nanoparticle concentration, energy, momentum and motile microorganism equations.Design/methodology/approachThe governing nonlinear coupled equations are first rendered into nonlinear ordinary equations using appropriate transformation and are then solved analytically by using the optimal homotopy.FindingsGraphical illustration of results depict the behavior of flow involved physical parameters on temperature, gyrotactic microorganism, concentration and velocity. Additionally, local Nusselt number and skin friction coefficient are computed numerically and validated through comparison with existing literature as a special case of proposed model. It is found that the temperature profile decreases by increasing values of Brownian-motion parameter and Prandtl number. An increase in thermophoresis parameter and Schmidt number results in decrease in concentration of nanoparticles. Bioconvection Peclet number corresponds to decreasing behavior of nondimensional gyrotactic microorganism field is observed. Finally, a comparison with the existing literature is made, and an excellent agreement is seen.Originality/valueTo the best of the authors’ knowledge, this study is reported for the first time.

Influences of Cattaneo-Christov Heat Flux, Joule Heating, Viscous Dissipation and Chemical Reaction on Hydromagnetic Pulsating Flow of Oldroyd-B Nanofluid in a Porous Channel

In this present study, Cattaneo-Christov heat flux on the hydromagnetic pulsatile flow of Oldroyd-B nanofluid through a porous channel with the presence of Brownian motion, thermal radiation, and thermophoresis effects are studied. The effects of dissipation of viscous and Ohmic heating are considered. The Buongiorno model is taken into account in this analysis. By using the perturbation method the governing partial differential equations (PDEs) are converted into the ordinary differential equations (ODEs) and solved numerically by employing the Runge-Kutta 4th-order scheme along with shooting approach. The influence of distinct parameters on velocity, temperature, nanoparticle concentration, heat and mass transfer rates are examined in detail. The results indicate that nanofluid velocity increases with higher frequency parameter, and while it falls with rising Hartmann number, and cross-flow Reynolds number. An increase in thermophoresis parameter, Eckert number, radiation parameter, Brownian motion parameter leads to a rise in temperature whereas temperature decreases for increasing Hartmann number and thermal relaxation time parameter. Moreover, the nanoparticle concentration enhances with an increasing thermophoresis parameter, thermal relaxation time parameter while it falls with the rising values of Lewis number, chemical reaction parameter and Brownian motion parameter.

Adomian Decomposition Method for the Radiative Micropolar Nanofluid Past a Porous Channel: An Analytical Approach

Present analysis leads to investigate the flow of conducting micropolar nanoliquid past a porous channel. The transverse magnetic field is imposed in the normal direction of the flow. The energy equation is enhanced by adopting the influence of thermal radiation. Similarity variable augmented with stream function is used to renovate PDES to ODEs. The present article's special desirability is the approximate analytical technique for these transformed governing equations. We have employed Adomian Decomposition Method (ADM). Descriptions of various profiles for the influence of different parameters are presented through graphs. However, the computation for the rate coefficients is also obtained and deliberated through the tabular form for the influence of diverse physical parameters. A significant contribution reveals that near the lower wall, heat transfer rate enhances greater thermal radiation while impact opposes at the upper wall. A comparison between the methodology newly adopted and the earlier solutions coincided with each other and was found to be in good agreement in particular cases. However, the major findings are laid down here as higher magnetic number favors enhancing angular velocity within the channel and fluid temperature increases due to an increase in thermophoresis parameter.

Study of 3-D Prandtl Nanofluid Flow over a Convectively Heated Sheet: A Stochastic Intelligent Technique

In this article, we examine the three-dimensional Prandtl nanofluid flow model (TD-PNFM) by utilizing the technique of Levenberg Marquardt with backpropagated artificial neural network (TLM-BANN). The flow is generated by stretched sheet. The electro conductive Prandtl nanofluid is taken through magnetic field. The PDEs representing the TD-PNFM are converted to system of ordinary differential equations, then the obtained ODEs are solved through Adam numerical solver to compute the reference dataset with the variations of Prandtl fluid number, flexible number, ratio parameter, Prandtl number, Biot number and thermophoresis number. The correctness and the validation of the proposed TD-PNFM are examined by training, testing and validation process of TLM-BANN. Regression analysis, error histogram and results of mean square error (MSE), validates the performance analysis of designed TLM-BANN. The performance is ranges 10−10, 10−10, 10−10, 10−11, 10−10 and 10−10 with epochs 204, 192, 143, 20, 183 and 176, as depicted through mean square error. Temperature profile decreases whenever there is an increase in Prandtl fluid number, flexible number, ratio parameter and Prandtl number, but temperature profile shows an increasing behavior with the increase in Biot number and thermophoresis number. The absolute error values by varying the parameters for temperature profile are 10−8 to 10−3, 10−8 to 10−3, 10−7 to 10−3, 10−7 to 10−3, 10−7 to 10−4 and 10−8 to 10−3. Similarly, the increase in Prandtl fluid number, flexible number and ratio parameter leads to a decrease in the concentration profile, whereas the increase in thermophoresis parameter increases the concentration distribution. The absolute error values by varying the parameters for concentration profile are 10−8 to 10−3, 10−7 to 10−3, 10−7 to 10−3 and 10−8 to 10−3. Velocity distribution shows an increasing trend for the upsurge in the values of Prandtl fluid parameter and flexible parameter. Skin friction coefficient declines for the increase in Hartmann number and ratio parameter Nusselt number falls for the rising values of thermophoresis parameter against Nb.

Dual solution framework for mixed convection flow of Maxwell nanofluid instigated by exponentially shrinking surface with thermal radiation

This paper presents the analysis of transfer of heat and mass characteristics in boundary layer flow of incompressible magnetohydrodynamic Maxwell nanofluid with thermal radiation effects confined by exponentially shrinking geometry. The effects of Brownian motion and thermophoresis are incorporated using Buongiorno model. The partial differential equations of the governing model are converted in non-dimensional track which are numerically inspected with proper appliances of Runge–Kutta fourth order scheme.The significant effects of heat and mass fluxes on the temperature and nanoparticles volume fractions are investigated. By the increases in Lewis number between 1.0 to 2.0, the decrease in nanoparticle volume fraction and temperature is noted. With the change in the Prandtl constant that varies between 0.7 to 1.5, the nanoparticles volume fraction and temperature are dwindled. Nanoparticles volume fraction and temperature distribution increase is noted with applications of radiation constant. With consequent variation of thermophoresis parameter between 0.1 to 0.8, nanoparticles volume fraction and temperature distribution increases. It is also noted that the increase in thermophoresis parameter and Brownian parameter from 0.1 to 0.8, nanoparticles volume fraction decreases while temperature distribution increases.

Bio-convective and chemically reactive hybrid nanofluid flow upon a thin stirring needle with viscous dissipation

In this work, the thermal analysis for bio-convective hybrid nanofluid flowing upon a thin horizontally moving needle is carried out. The chemical reaction and viscous dissipation has also considered for flow system in the presence of microorganism. The hybrid nanoparticles comprising of Copper left( {Cu} right) and Alumina left( {Al_{2} O_{3} } right) are considered for current flow problem. Mathematically the flow problem is formulated by employing the famous Buongiorno’s model that will also investigate the consequences of thermophoretic forces and Brownian motion upon flow system. Group of similar variables is used to transform the model equations into dimensionless form and have then solved analytically by homotopy analysis method (HAM). It has established in this work that, flow of fluid declines due to increase in bioconvection Rayleigh number, buoyancy ratio and volume fractions of nanoparticles. Thermal flow grows due to rise in Eckert number, Brownian, thermophoresis parameters and volume fraction of nanoparticles. Concentration profiles increase due to growth in Brownian motion parameter and reduces due to increase in thermophoresis parameter and Lewis number. Motile microorganism profile declines due to augmentation in Peclet and bioconvection Lewis numbers. Moreover, the percentage enhancement in the drag force and rate of heat transfer using conventional nanofluid and hybrid nanofluid are observed and discussed. The hybrid nanofluid increases the skin friction and heat transfer rate more rapidly and efficiently as compared to other traditional fluids. A comparison of the present study with the existing literature is also conducted with a closed agreement between both results for variations in thickness of the needle.

MHD Stagnation Point Flow of Nanofluid on a Plate with Anisotropic Slip

In this article, an axisymmetric three-dimensional stagnation point flow of a nanofluid on a moving plate with different slip constants in two orthogonal directions in the presence of uniform magnetic field has been considered. The magnetic field is considered along the axis of the stagnation point flow. The governing Naiver–Stokes equation, along with the equations of nanofluid for three-dimensional flow, are modified using similarity transform, and reduced nonlinear coupled ordinary differential equations are solved numerically. It is observed that magnetic field M and slip parameter λ 1 increase the velocity and decrease the boundary layer thickness near the stagnation point. Also, a thermal boundary layer is achieved earlier than the momentum boundary layer, with the increase in thermophoresis parameter N t and Brownian motion parameter N b . Important physical quantities, such as skin friction, and Nusselt and Sherwood numbers, are also computed and discussed through graphs and tables.

Numerical study of Carreau nanofluid flow past vertical plate with the Cattaneo–Christov heat flux model

PurposeTo achieve material-invariant formulation for heat transfer of Carreau nanofluid, the effect of Cattaneo–Christov heat flux is studied on a natural convective flow of Carreau nanofluid past a vertical plate with the periodic variations of surface temperature and the concentration of species. Buongiorno model is considered for nanofluid transport, which includes the relative slip mechanisms, Brownian motion and thermophoresis.Design/methodology/approachThe governing equations are non-dimensionalized using suitable transformations, further reduced to non-similar form using stream function formulation and solved by local non-similarity method with homotopy analysis method. The numerical computations are validated and verified by comparing with earlier published results and are found to be in good agreement.FindingsThe effects of varying the physical parameters such as Prandtl number, Schmidt number, Weissenberg number, thermophoresis parameter, Brownian motion parameter and buoyancy ratio parameter on velocity, temperature and species concentration are discussed and presented through graphs. The results explored that the velocity of shear thinning fluid is raised by increasing the Weissenberg number, while contrary response is seen for the shear thickening fluid. It is also found that heat transfer in Cattaneo–Christov heat conduction model is less than that in Fourier’s heat conduction model. Furthermore, the temperature and thermal boundary layer thickness expand with the increase in thermophoresis and Brownian motion parameter, whereas nanoparticle volume fraction increases with increase in thermophoresis parameter, but reverse trend is observed with increase in Brownian motion parameter.Originality/valueThe present investigation is relatively original as very little research has been reported on Carreau nanofluids under the effect of Cattaneo–Christov heat flux model.

Numerical study of nanofluid flow and heat transfer over a rotating disk using Buongiorno’s model

PurposeThe purpose of the present study is to explore a three-dimensional rotating flow of water-based nanofluids caused by an infinite rotating disk.Design/methodology/approachMathematical formulation is performed using the well-known Buongiorno model which accounts for the combined influence of Brownian motion and thermophoresis. The recently suggested condition of passively controlled wall nanoparticle volume fraction has been adopted.FindingsThe results reveal that temperature decreases with an increase in thermophoresis parameter, whereas it is negligibly affected with a variation in the Brownian motion parameter. Axial velocity is negative because of the downward flow in the vertical direction.Originality/valueTwo- and three-dimensional streamlines are also sketched and discussed. The computations are found to be in very good agreement with the those of existing studies in the literature for pure fluid.

Thermal radiation impact in mixed convective peristaltic flow of third grade nanofluid

Abstract This paper models the peristaltic transport of magnetohydrodynamic (MHD) third grade nanofluid in a curved channel with wall properties. Combined effects of heat and mass transfer are retained via mixed convection. The present analysis is made in the presence of thermal radiation and chemical reaction. No-slip effect is maintained at the boundary for the velocity, temperature and nanoparticle volume fraction. Resulting formulation is simplified by employing the assumptions of long wavelength and low Reynolds number approximations. Results of axial velocity, temperature, nanoparticle mass transfer and heat transfer are studied graphically. Results reveal increment in fluid velocity for larger values of heat transfer Grashof number. There is reduction in nanoparticle mass transfer with the increase in thermophoresis parameter.

Nonlinear thermal radiation in three-dimensional flow of Jeffrey nanofluid: A model for solar energy

This article explores the characteristics of thermophoresis and Brownian motion in magnetohydrodynamic three-dimensional flow of nano Jeffrey fluid. Flow analysis is modeled in the presence of thermal radiation. The resulting stretched flow problems have been solved for the velocity, temperature and concentration. The constructed expressions depend upon ratio of relaxation to retardation times, Deborah number, magnetic parameter, ratio of stretching rates, Lewis number, Prandtl number, radiation parameter, thermophoresis and Brownian motion parameters. Plots are presented and analyzed specifically for the temperature and nanoparticle concentration profiles. Numerical computations are performed for local Nusselt and Sherwood numbers. Impact reflecting the contributions of various embedded on the local Nusselt and Sherwood numbers is point out. It is observed that temperature and nanoparticle concentration profiles are decreased with an increase in Deborah number. An increase in thermophoresis parameter shows rise to the temperature and nanoparticle concentration fields. It is also seen that temperature and nanoparticle concentration profiles are quite opposite when Brownian motion parameter is increased.

MHD flow of Jeffrey nanofluid with convective boundary conditions

This article investigates the effects of convective heat and concentration conditions in magnetohydrodynamic flow of non-Newtonian fluid with nanoparticles. Convective type boundary conditions are utilized for heat and nanoparticles concentration. The nonlinear partial differential equations are reduced into the nonlinear ordinary differential equations by suitable similarity variables. Homotopy analysis method is employed to obtain the dimensionless velocity, temperature and nanoparticles concentration expressions. Graphical results for temperature and nanoparticles concentration are plotted and examined. Numerical values of skin friction coefficient are computed and discussed. Heat transfer and nanoparticles concentration transfer rates at the wall are examined by plotting the graphs of different governing physical parameters. We noticed that the temperature and nanoparticles concentration profiles are enhanced when the values of Biot numbers are increased. An increase in thermophoresis parameter leads to an enhancement in the temperature and nanoparticles concentration. On the other hand the increasing values of Brownian motion parameter has reverse effects on the temperature and nanoparticles concentration fields.