Double-diffusive Nanofluid Research Articles

Exploring double-diffusive nanofluid flow in divergent/convergent nondarcy porous space: A machine learning numerical approach with zero mass flux

In this study, authors address the problem of analyzing the Jeffrey–Hamel nanofluid flow within a nonparallel channel under the influence of a thermally balanced non-Darcy permeable medium. Our objective is to explore the behavior of the nanofluid, employing the Buongiorno nanofluid model, and considering factors such as zero mass flux conditions, variable rheological fluid properties, and the presence of temperature jump phenomena through ANN-PSO-NNA. To tackle this intricate issue, propose a novel approach using Artificial Neural Networks (ANN) integrated with particle swarm optimization (PSO) hybrid with neural network algorithm (NNA). This combined technique is referred to as ANN-PSO-NNA. The governing flow equations based on the Jeffrey–Hamel analysis are first transformed into dimensionless forms. To establish the efficacy of our approach compare it with the widely used NDSolve method. Furthermore, the study presents the absolute error analysis for four distinct cases offering a quantitative assessment of the accuracy of ANN-PSO-NNA. The absolute error between the NDsolve and the proposed ANN-PSO-NNA is given for four different cases, ranging from 1.95E-06 to 1.18E-08. The biases and weights obtained through proposed method range from −10 to 10. This enables us to gauge the performance of the ANN-PSO-NNA minimum values of the fitness function 2.37E-08, 2.30E-08, 3.92E-08, and 1.22E-08 from multiple independent runs, which are showcased to be convergent, underscoring the robustness of the ANN-PSO-NNA approach. Employing graphical representations, explores the influence of various parameters on the velocity and temperature profiles. Our integrated approach offers a comprehensive understanding of the underlying dynamics, paving the way for optimized designs and enhanced efficiency across these diverse engineering applications.

Numerical analysis of non-Newtonian nanofluids under double-diffusive regimes

In the present study, the slip velocity of a non-Newtonian fluid flowing above a continuously stretching surface with double-diffusive nanofluid is examined at prespecified values of surface temperature, while also accounting for salt concentration. An initial set of partial differential equations, along with the boundary conditions, are first cast into a dimensionless form; subsequently, the comparation variables are invoked to reduce the partial differential equations to ordinary differential equations; and finally, the reduced ordinary differential equations are solved numerically via the shooting method. Values for dimensionless velocity, temperature, salt concentration distribution, local Nusselt number, and Sherwood number are calculated numerically and presented visually in a set of graphs. A extensive parametric study is conducted to probe the effects of adjusting various parameters in the cases of both assisting and opposing flow.

Dynamics of multiple slip boundaries effect on MHD Casson-Williamson double-diffusive nanofluid flow past an inclined magnetic stretching sheet

The present research paper highlights the effect of multiple slips and inclined magnetic fields on chemically reacting Casson-Williamson with Buongiorno modeled nanofluid flow past a permeable stretching surface. Considered physical factors associated with heat transfer are viscous dissipation, Joule's heating, radiation, and double diffusion effects. The ordinary differential equations (ODEs) are formulated from governing system of highly nonlinear Partial differential equations (PDEs) by a suitable implementation of similarity invariants. The numerical results are obtained by programming the resulting equations in MATLAB software via Runge-Kutta (R-K) fourth-order technique along with the shooting scheme. The graphical illustration provides the behavior of velocity, temperature, and concentration on different non-dimensional parameters. It is worth to notice the slip parameters are greatly analogs with various physical properties of the flow field. The effect of a magnetic parameter ([Formula: see text]), Casson parameter ([Formula: see text]), Williamson parameter ([Formula: see text]), velocity slip effect ([Formula: see text]), and the inclination ([Formula: see text]) on axial velocity are shown graphically. The outstanding agreement is observed after a comparison of numerical outcomes with previously published work. The applied magnetic field and thermal radiation insert more energy into the system which improves the thermal boundary layer.

Effects of dissolved solute on unsteady double-diffusive mixed convective flow of a Buongiorno’s two-component nonhomogeneous nanofluid

PurposeThe purpose of this paper is to numerically study the unsteady double-diffusive mixed convective stagnation-point flow of a water-based nanofluid accompanied with one salt past a vertical flat plate. The effects of Brownian motion and thermophoresis parameters are also introduced through Buongiorno’s two-component nonhomogeneous equilibrium model in the governing equations.Design/methodology/approachIn the present explanation of double-diffusive mixed convective model, there are four boundary layers entitled: velocity, thermal, solutal concentration and nanoparticle concentration. The resulting basic equations are solved numerically via an efficient Runge–Kutta fourth-order method with shooting technique after the governing nonlinear partial differential equations are converted into a system of nonlinear ordinary differential equations by the use of similarity transformations.FindingsTo avail the physical insight of problem, the effects of the mixed convection parameter, unsteadiness parameter and salt/nanoparticle parameters on the boundary layers behavior are investigated. Moreover, four possible types of diffusion problems entitled: double-diffusive nanofluid (DDNF), double-diffusive regular fluid (DDRF), mono-diffusive nanofluid (MDNF) and mono-diffusive regular fluid (MDRF) are considered to analyze and compare them in concepts of heat and mass transfer.Originality/valueThe results demonstrate that, for a regular fluid, without nanoparticle and salt (MDRF), the dimensionless heat transfer rate is smaller than other diffusion cases. As we include nanoparticle and salt (DDNF), the rate of heat transfer increases due to an increase in thermal conductivity and rate of diffusion of salt. Moreover, it is observed that the highest heat transfer rate is obtained for the situation that the thermophoretic effect of nanoparticles is negligible. Besides, the heat transfer rate enhances with the increase in the regular double-diffusive buoyancy parameter of salt.

Double-Diffusive Nanofluid Convection in Porous Medium with Rotation: Darcy-Brinkman Model

In this paper, we have studied the onset of convection in a rotating binary nanofluid layer saturated by a porous medium using Darcy-Brinkman model. Normal mode technique and Galerkin type weighted residual method are used to solve conservation equations. For analytical study, valid approximations are made in the complex equations for oscillatory convection to get useful results. Top heavy distribution of nanoparticles destabilizes the layer significantly and oscillatory motions are not possible. The problem is studied numerically for water based nanofluids with alumina, copper and silver nanoparticles using Mathematica software and results are shown graphically. The Coriolis force term due to the presence of rotation stabilizes the system while Darcy number destabilizes/stabilizes the layer for small/large values of wave number.

The Cheng–Minkowycz problem for the double-diffusive natural convective boundary layer flow in a porous medium saturated by a nanofluid

The paper presents an analytical treatment of double-diffusive nanofluid convection in a porous medium. The problem treated is natural convection past a vertical plate when the base fluid of the nanofluid is itself a binary fluid such as salty water. The model used for the nanofluid incorporates the effects of Brownian motion and thermophoresis, while the Darcy model is used for the porous medium. In addition the thermal energy equations include regular diffusion and cross-diffusion terms. A similarity solution is presented.

The Onset of Double-Diffusive Nanofluid Convection in a Layer of a Saturated Porous Medium

The paper develops a theory of double-diffusive nanofluid convection in porous media. This theory is applied to investigating the onset of nanofluid convection in a horizontal layer of a porous medium saturated by a nanofluid for the case when the base fluid of the nanofluid is itself a binary fluid such as salty water. The model used for the nanofluid incorporates the effects of Brownian motion and thermophoresis, while the Darcy model is used for the porous medium. In addition the thermal energy equations include regular diffusion and cross-diffusion terms. Both non-oscillatory and oscillatory cases are investigated by using Galerkin method; the stability boundaries for these cases are approximated by simple and useful analytical expressions.