Niki Rezazadeh, Rezvan Abdi^*

Frontiers in Heat and Mass Transfer, Vol.7, pp. 1-6, 2016, DOI:10.5098/hmt.7.30

Abstract This study investigates the heat transfer in the mode of natural convection from a pair of hot cylinders to a cold square enclosure. Effects of boundary conditions of the enclosure on the rate of heat transfer from a pair of isothermal hot cylinders are investigated at a Rayleigh number of 10⁵ . The cylinders are arranged in a horizontal array at the middle height of enclosure. The commercial software, Fluent (V.6.3.26), is utilized to solve the problem using the Finite Volume Method. The streamlines as well as isothermal lines of the problem are reported. Moreover, the local Nusselt number on… More >

K. Venkatadri^a,*, S. Gouse Mohiddin^a , M. Suryanarayana Reddy^b

Frontiers in Heat and Mass Transfer, Vol.9, pp. 1-9, 2017, DOI:10.5098/hmt.9.33

Abstract Two-dimensional unsteady laminar double-diffusive free convective flow of a conducting fluid in a thermally insulated square enclosure except the left wall has been numerically studied in presence of heat generation/absorption. The Marker and Cell (MAC) method is employed for solving nonlinear momentum, energy and concentration equations and the numerical MATLAB code is validated with the previous study. The computed results are depicted graphically and discussed for various values of Rayleigh number (Ra), Hartmann number (Ha), Buoyancy ratio parameter (N), Lewis number (Le) and heat absorption/generation parameter (γ). It is observed that the rate of heat and mass transfer decreases with… More >

Mahmud H. Ali^a,* , Rawand E. Jalal^a

Frontiers in Heat and Mass Transfer, Vol.15, pp. 1-14, 2020, DOI:10.5098/hmt.15.27

Abstract In this work, natural convection in an adiabatic enclosure with openings induced by two isothermal hot cylinders is approached numerically. The study covers five different configurations of the enclosure as the number and locations of the inlet and outlet ports are varied for Rayleigh number (Ra) between 10⁴ and 10⁶ . Additionally, the study also analyzes the effects of varying the horizontal distance (S) between the cylinders along with their vertical locations () for dimensionless values of 0.4 to 0.3 and -0.2 to 0.2, respectively, at a constant Ra of 10⁶ . The outcomes show that the locations of the… More >

Farah Zemani-Kaci^*, Amina Sabeur-Bendhina

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.2, pp. 513-539, 2023, DOI:10.32604/fdmp.2022.021974

Abstract A two-dimensional numerical study of laminar natural convection in a square enclosure filled with air with a wall partially heated on the bottom is presented. The heat source is located on the lower wall with different heated widths varied from 20 to 80%(ε = 0.2–0.8) of the total width of the lower wall and different heights h = H/4 and H/2 of the partition. The effect of the partition height on the main system dynamics is investigated through solution of the two-dimensional Navier–Stokes equations and the energy equation by means of a finite volume method based on the SIMPLE algorithm.… More > Graphic Abstract

Latifa M. Al-Balushi, M. M. Rahman^*

FDMP-Fluid Dynamics & Materials Processing, Vol.16, No.3, pp. 441-463, 2020, DOI:10.32604/fdmp.2020.08551

Abstract In the present paper, the effect of the heat flux distribution on the natural convective flow inside a square cavity in the presence of a sloping magnetic field and magnetic nanoparticles is explored numerically. The nondimensional governing equations are solved in the framework of a finite element method implemented using the Galerkin approach. The role played by numerous model parameters in influencing the emerging thermal and concentration fields is examined; among them are: the location of the heat source and its lengthH*, the magnitude of the thermal Rayleigh number, the nanoparticles shape and volume fraction, and the Hartmann number. It… More >

Ridha Djebali^1,2, Bernard Pateyron², Mohamed El Ganaoui³

CMES-Computer Modeling in Engineering & Sciences, Vol.88, No.4, pp. 293-308, 2012, DOI:10.3970/cmes.2012.088.293

Abstract We present in this study a numerical investigation of unsteady two-dimensional natural convection of an electrically conducting fluid in a square cavity under an externally imposed magnetic field. A temperature gradient is applied between the two opposing side walls parallel to y-direction, while the floor and ceiling parallel to x-direction are adiabatic. The flow is characterized by the Rayleigh number Ra raged in 103-106, the Prandtl number Pr ranged in 0.01-10, the Hartman number Ha determined by the strength of the imposed magnetic field ranged in 0-100 and its tilting angle from x-axis ranging from 0 to 90 . The… More >

Taoufik Naffouti^1,2 and Ridha Djebali^1,3

CMES-Computer Modeling in Engineering & Sciences, Vol.88, No.3, pp. 211-228, 2012, DOI:10.3970/cmes.2012.088.211

Abstract This paper reports numerical results of natural convection flow evolving inside confined medium defined by two-dimensional square enclosure containing isothermal hot source placed asymmetrically at bottom wall. The sides-walls are isothermally cooled at a constant temperature; however the ceiling and the rest of bottom wall are insulated. The lattice Boltzmann method is used to solve the dimensionless governing equations with the associated boundary conditions. The flow is monitored by the Grashof number and the Prandtl number taken here 0.71. Numerical simulations are performed to study the effects of Grashof number ranging from 104 to 106, hot source length from 0.1… More >

Ridha Djebali^1,2, Mohamed ElGanaoui³, Taoufik Naffouti¹

CMES-Computer Modeling in Engineering & Sciences, Vol.84, No.6, pp. 499-527, 2012, DOI:10.3970/cmes.2012.084.499

Abstract A thermal lattice Boltzmann model for incompressible flow is developed and extended to investigate the natural convection flow in porous media under the effect of uniform magnetic field. The study shows that the flow behaviour is various parameters dependent. The Rayleigh number (Ra), Hartmann number (Ha), Darcy number (Da) and the medium inclination angle from the horizontal (Φ), the magnetic field orientation (ψ) and the medium porosity (ε) effects are carried out in wide ranges encountered in industrial and engineering applications. It was found that the flow and temperature patterns change significantly when varying these parameters. To confirm the accuracy… More >

Hamici Nadjib¹, Sahi Adel^1,*, Sadaoui Djamel¹, Djerrada Abderrahmane¹

FDMP-Fluid Dynamics & Materials Processing, Vol.14, No.3, pp. 155-175, 2018, DOI: 10.3970/fdmp.2018.01114

Abstract The study goes further to investigate a two-dimensional numerical model coupling free convection and surface radiation in an air-filled cavity containing a heated thin finned plate. The square enclosure is subjected to isothermal and insulated boundary conditions while the heating element location is varied from the horizontal position (HPFU, HPFD) to the vertical position (VPFL). The dimensionless governing equations under Boussinesq approximations are coupled with a radiative model through the boundaries conditions and solved by the Finite Volume Method. The effects of the pertinent parameters, namely, Rayleigh number (10³≤Ra≤10⁶), fin length (0.125≤L_a≤0.875), fin position (0.25≤H_a≤0.75) and wall emissivity (0≤ε≤1) are… More >