M. Kriaa¹, M. El Alami^1,2, M. Najam¹, E. Semma³

FDMP-Fluid Dynamics & Materials Processing, Vol.7, No.2, pp. 125-140, 2011, DOI:10.3970/fdmp.2011.007.125

Abstract In this paper a numerical study of natural convection in a two dimensional convergent channel, with or without rectangular block, is carried out. The block is placed at the channel outlet and its thermal conductivity is set equal to that of air. One of channel planes is heated at constant temperature T_H. The other one is maintained cold at T_C < T_H. The governing equations are solved using a finite volume method and the SIMLEC algorithm for the velocity-pressure coupling is used. Special emphasis is given to detail the effect of the block size and Rayleigh number on the dynamics… More >

Hicham Rouijaa¹, Mustapha El Alami², El Alami Semma³, Mostafa Najam²

FDMP-Fluid Dynamics & Materials Processing, Vol.7, No.1, pp. 57-70, 2011, DOI:10.3970/fdmp.2011.007.057

Abstract This article presents a numerical study on natural convection in a bidimensional inclined "T"-shaped cavity. The governing equations are solved in the framework of a control-volume method resorting to the SIMPLEC algorithm (for the treatment of pressure-velocity coupling). Special emphasis is given to the investigation of the effect of inclination on the heat transfer and mass flow rate. Results are discussed for Prandtl number Pr=0.72, geometry with: opening width C=0.15, blocks gap D=0.5, blocks height, B=0.5 and different values of the Rayleigh number (10⁴ ≤ Ra ≤ 10⁶). More >

M. El Alami¹, E. A. Semma^2,3, M. Najam¹, R. Boutarfa²

FDMP-Fluid Dynamics & Materials Processing, Vol.5, No.1, pp. 23-36, 2009, DOI:10.3970/fdmp.2009.005.023

Abstract This study is devoted to the investigation of natural convection in a two dimensional horizontal channel with rectangular heated blocks at the bottom. The aspect ratio of the channel is A = L'/H' = 5. The blocks are heated with a constant temperature while the upper plane of the channel is cold. The governing equations are solved using a finite volumes method and the SIMPLEC algorithm is used for the treatment of the pressure-velocity coupling. Special emphasis is given to detail the effect of the Rayleigh number and blocks height on the heat transfer and the mass flow rate generated… More >

K. Achoubir¹, R. Bennacer², A. Cheddadi¹, M. El Ganaoui³, E. Semma^3,4

FDMP-Fluid Dynamics & Materials Processing, Vol.4, No.3, pp. 199-210, 2008, DOI:10.3970/fdmp.2008.004.199

Abstract The present work is devoted to the numerical investigation of the interaction between thermal and solutal convection in enclosures used for modeling directional solidification. The full transient Navier--Stokes, energy and species conservation equations are solved numerically by using finite volumes technique. More >

Y. Okano¹, A. Ishii¹, H. Miyashita¹, H. Minakuchi¹, S. Dost²

FDMP-Fluid Dynamics & Materials Processing, Vol.2, No.4, pp. 261-270, 2006, DOI:10.3970/fdmp.2006.002.261

Abstract The article presents the results of a numerical simulation study that was carried out to examine the effect of g-jitter on the flow and concentration structures observed in the solution of a growth crucible under microgravity conditions. The simulation model considers a simple crucible of electroepitaxy, and assumes crucible rotation and applied axial static magnetic fields to control and minimize the effect of g-jitter induced flow oscillations. More >

Ahmed Mahmoudi^1,2, Imen Mejri¹, Mohamed Ammar Abbassi¹, Ahmed Omri¹

FDMP-Fluid Dynamics & Materials Processing, Vol.9, No.4, pp. 353-388, 2013, DOI:10.3970/fdmp.2013.009.353

Abstract A double-population Lattice Boltzmann Method (LBM) is applied to solve the steady-state laminar natural convective heat-transfer problem in a triangular cavity filled with air (Pr = 0.71). Two different boundary conditions are implemented for the vertical and inclined boundaries: Case I) adiabatic vertical wall and inclined isothermal wall, Case II) isothermal vertical wall and adiabatic inclined wall. The bottom wall is assumed to be at a constant temperature (isothermal) for both cases. The buoyancy effect is modeled in the framework of the well-known Boussinesq approximation. The velocity and temperature fields are determined by a D2Q9 LBM and a D2Q4 LBM,… More >

O. Mahrouche¹, M. Najam¹, M. El Alami^1,2, M. Faraji¹

FDMP-Fluid Dynamics & Materials Processing, Vol.9, No.3, pp. 235-250, 2013, DOI:10.3970/fdmp.2013.009.235

Abstract Mixed convection in a rectangular partitioned cavity equipped with two heated partitions at a constant temperature, T_C, is investigated numerically. The right vertical wall is featured by two openings (C₁ and C₂) for admission of cooled air along the horizontal direction, while the lower wall has a single outlet opening (C₃) along the vertical axis. The left vertical wall is assumed to be isothermal at temperature T_C, while the other walls are cooled to a temperature T_F < T_C. The results show that the flow and heat transfer depend significantly on Reynolds number, Re, and block height, B. Correlation laws… More >

S. Guenoun¹, A. Baïri¹, N. Laraqi^1,2, J.M. García de María³, J.G. Bauzin¹, A. Hocine¹

FDMP-Fluid Dynamics & Materials Processing, Vol.8, No.2, pp. 197-214, 2012, DOI:10.3970/fdmp.2012.008.197

Abstract Roller bearings are used in mechanical setups to reduce rubbing. In some applications, the thermal dissipation involved mostly due to friction between rollers and rings is important. Correct operation of the roller is possible only if local thermal phenomena are controlled. In this work, the resulting dynamical and thermal fields within the enclosures limited by rollers and rings in cylindrical bearings are obtained through numerical modelling. Convective heat transfer is quantified by Nu-Re-Pr correlations for various dynamical and thermal configurations of the bearing. Two specific shape factors of the cavity and common fluids of engineering interest are considered, including air,… More >

F. Moufekkir¹, M.A. Moussaoui¹, A. Mezrhab^1,2, H. Naji^3,4, M. Bouzidi⁵

FDMP-Fluid Dynamics & Materials Processing, Vol.8, No.2, pp. 129-154, 2012, DOI:10.3970/fdmp.2012.008.129

Abstract The problem related to coupled double diffusive convection in a square enclosure filled with a gray gas in the presence of volumetric radiation is examined numerically. The horizontal walls are assumed to be insulated and impermeable. Different temperatures and species concentrations are imposed at vertical walls. In particular, we propose a 2-D numerical approach based on a hybrid scheme combining a multiple-relaxation-time lattice Boltzmann model (MRT-LBM) and a standard finite difference method (FDM). The radiative term in the energy equation is treated using the discrete ordinates method (DOM) with a S8 quadrature. The influence of various parameters (such as the… More >

Evgeny V. Votyakov¹, Egbert A. Zienicke¹

FDMP-Fluid Dynamics & Materials Processing, Vol.3, No.2, pp. 97-114, 2007, DOI:10.3970/fdmp.2007.003.097

Abstract We simulated numerically the laminar flow in the geometry and the magnetic field of the experimental channel used in [Andreev, Kolesnikov, and Thess (2006)]. This provides detailed information about the electric potential distribution for the laminar regime (numerical simulation) and in the turbulent regime as well (experiment). As follows from comparison of simulated and experimental results, the flow under the magnet is determined by the interaction parameter N = Ha² / Re representing the ratio between magnetic force, determined by the Hartmann number Ha, and inertial force, determined by the Reynolds number Re. We compared two variants: (i)(Re,N)=(2000,18.6) (experiment), (400,20.25)… More >