N. Freidoonimeh

Bio: N. Freidoonimeh is an academic researcher from Tongji University. The author has contributed to research in topics: Mass transfer coefficient & Herschel–Bulkley fluid. The author has an hindex of 1, co-authored 1 publications receiving 13 citations.

Two parameters Lie group analysis and numerical solution of unsteady free convective flow of non-Newtonian fluid

Abstract: The two-dimensional unsteady laminar free convective heat and mass transfer fluid flow of a non-Newtonian fluid adjacent to a vertical plate has been analyzed numerically. The two parameters Lie group transformation method that transforms the three independent variables into a single variable is used to transform the continuity, the momentum, the energy and the concentration equations into a set of coupled similarity equations. The transformed equations have been solved by the Runge–Kutta–Fehlberg fourth-fifth order numerical method with shooting technique. Numerical calculations were carried out for the various parameters entering into the problem. The dimensionless velocity, temperature and concentration profiles were shown graphically and the skin friction, heat and mass transfer rates were given in tables. It is found that friction factor and heat transfer (mass transfer rate) for methanol are higher (lower) than those of hydrogen and water vapor. Friction factor decreases while heat and mass transfer rate increase as the Prandtl number increases. Friction (heat and mass transfer rate) factor of Newtonian fluid is higher (lower) than the dilatant fluid.

Numerical investigation of MHD nanofluid free convective heat transfer in a porous tilted enclosure

Abstract: Purpose The effect of a magnetic field on nanofluid natural convection in a porous annulus is simulated. Control volume-based finite element method (CVFEM) is applied to find the influence of tilted angle and Darcy, Rayleigh and Hartmann numbers on nanofluid hydrothermal behavior. Vorticity stream function formulation is taken into account. Also, Brownian motion effect on nanofluid thermal conductivity is considered. Results reveal that Hartmann number and tilted angle make changes in nanofluid flow style. Nusselt number enhances with augment of Darcy number and buoyancy forces but reduces with rise of tilted angle and Hartmann number. Design/methodology/approach The influence of adding CuO nanoparticles in water on the velocity and temperature distribution in an inclined half-annulus was studied considering constant heat flux. CVFEM is applied to the simulation procedure. Findings Influences of CuO volume fraction, inclination angle and Rayleigh number on hydrothermal manners are presented. Originality/value Results indicate that inclination angle makes changes in flow style. The temperature gradient enhances with rise of buoyancy forces, whereas it reduces with augment of inclination angle.

Intelligent computing strategy to analyze the dynamics of convective heat transfer in MHD slip flow over stretching surface involving carbon nanotubes

Abstract: The research work presents the dynamics of system based on the model of convective heat transfer in Magnetodydrodynamics (MHD) slip flow over stretching surface with single-wall carbon nanotubes (CNTs) by exploiting the strengths of intelligent computing procedures including artificial neural networks (ANNs), genetic algorithms (GAs) and sequential quadratic technique (SQP). Using similarity transformation, the boundary layer mechanism for the baseline nanofluidics system modeled by partial differential equations (PDEs) is reduced to coupled ordinary differential equations (ODEs). The transformed system is modeled in an unsupervised manner with feed-forward ANNs and efficient adaptation of these networks is performed with global search optimization using GA, aided with SQP for local search. The proposed scheme is evaluated to analyze the dynamics of nanofluidics by taking different concentrations of single-wall CNTs based nano-materials mixed with base fluids such as water, kerosene oil or engine oil. Reliability and correctness of the proposed scheme is established through simulation experiments with results which consistently match with Adams numerical procedure. Moreover, Monte Carlo simulations based statistical analysis has been performed to validate the accuracy of the results in terms of performance metrics of variance account for (VAF), mean absolute error (MAE) and root mean square error (RMSE).

Influence of chemical reaction on MHD couple stress nanoliquid flow over a bidirectional stretched sheet

Abstract: A mathematical model has been established to study the effect of heat source on magnetohydrodynamic 3D chemically reacting couple stress nanofluid flow generated due to the stretching surface. The ...

Influence of the chamber inclination angle and heat-generating element location on thermal convection of power-law medium in a chamber

Abstract: This paper aims to study the mathematical modeling of passive cooling systems for electronic devices. Improving heat transfer is facilitated by the correct choice of the working fluid and the geometric configuration of the engineering cavity; therefore, this work is devoted to the analysis of the influence of the position of the heat-generating element and the tilted angle of the electronic cabinet on the thermal convection of a non-Newtonian fluid.,The area of interest is a square cavity with two cold vertical walls, while the horizontal boundaries are adiabatic. An element of constant volumetric heat generation is placed on the lower wall of the chamber. The problem is described by Navier–Stokes partial differential equations using dimensionless stream function and vorticity. The numerical solution is based on the developed computational code using the finite difference technique and a uniform rectangular grid.,The key conclusions of this work are the results of a detailed analysis of streamlines and isotherms, the average Nusselt number and profiles of the average heater temperature. It was found that more intensive cooling of the heat-generating element occurs when the cavity is filled with a pseudoplastic fluid (n < 1) and not inclined (α = 0). The Rayleigh number of Ra = 105 and the thermal conductivity ratio of k = 100 are characterized by the most positive effect.,The originality of the research lies in both the study of thermal convection in a square chamber filled with power-law fluid under the influence of a volumetric heat production element and the analysis of the influence of geometric and thermophysical parameters characterizing the considered process.

Exact analysis of MHD flow of a Walters'-B fluid over an isothermal oscillating plate embedded in a porous medium

Abstract: This paper carries out an exact analysis of the MHD free convection flow of a Walters'-B fluid over an oscillating isothermal vertical plate embedded in a porous medium. Exact solutions are produced for velocity, temperature and concentration with the aid of the Laplace transform technique. Similarly, at the wall, the corresponding shear stress is also calculated from the velocity expression. The obtained results confirm an excellent agreement with previously published work. The influence of various pertinent parameters is plotted and illustrated graphically. Finally, the numerical results for the skin friction are exhibited in tabular form.