R. C. Bataller¹

FDMP-Fluid Dynamics & Materials Processing, Vol.7, No.2, pp. 153-174, 2011, DOI:10.3970/fdmp.2011.007.153

Abstract We present a numerical study of the flow and heat transfer of an incompressible upper-convected Maxwell (UCM) fluid in the presence of an uniform transverse magnetic field over a porous stretching sheet taking into account suction at the surface as well as viscous dissipation and thermal radiation effects. Selected similarity analyses have been carried out by means of a numerical implementation. The effects on the velocity and temperature fields over the sheet of the parameters like elasticity number, suction velocity, magnetic parameter, radiation parameter, Prandtl number and Eckert number are also analyzed. More >

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 >

Ahmed Meskini, Mostafa Najam, Mustapha El Alami

FDMP-Fluid Dynamics & Materials Processing, Vol.7, No.1, pp. 97-110, 2011, DOI:10.3970/fdmp.2011.007.097

Abstract A numerical mixed convection investigation was carried out to study the enhancement of heat transfer in a square cavity with identical heated rectangular blocks adjacent to its upper wall, and submitted to a vertical jet of fresh air from below. The configuration so defined is an inverted "T"-shaped cavity presenting symmetry with respect to a vertical axis passing by the middle of the openings. The governing equations have been solved using the finite difference method. The parameters of this study are: Rayleigh number 10⁴ ≤ Ra ≤ 10⁶, Reynolds number 1 ≤ Re ≤ 1000, the opening width C=0.15, the… More >

Shaligram Tiwari¹, Koichi Nishino²

FDMP-Fluid Dynamics & Materials Processing, Vol.6, No.1, pp. 109-136, 2010, DOI:10.3970/fdmp.2010.006.109

Abstract The present work reports about an experimental study investigating the influence of air convection and of ambient temperature around a half-floating zone on the transition behavior from steady to oscillatory flow, i.e. the influence on the critical Marangoni number (Macr). Increase of heat loss from the free surface of the half-floating zone or liquid bridge by increased convection and ambient cooling decreases Macr. Heat input to the free surface increases Macr. An add-on numerical simulation of the air convection around the zone clarifies the influence of air convection and the ambient temperature on the temperature, surface velocity and local Biot… More >

Ahmed Mezrhab¹, Hassan Naji²

FDMP-Fluid Dynamics & Materials Processing, Vol.5, No.3, pp. 283-296, 2009, DOI:10.3970/fdmp.2009.005.283

Abstract The objective of this paper is to assess the effectiveness of the coupled Lattice Boltzmann Equation (LBE) and finite volume method strategy for the simulation of the interaction between thermal radiation and laminar natural convection in a differentially heated square cavity. The vertical walls of the cavity are adiabatic, while its top and bottom walls are cold and hot, respectively. The air velocity is determined by the lattice Boltzmann equation and the energy equation is discretized by using a finite volume method. The resulting systems of discretized equations have been solved by an iterative procedure based on a preconditioned conjugate… 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 >

R. Henda¹, W. Quesnel², Z. Saghir³

FDMP-Fluid Dynamics & Materials Processing, Vol.4, No.4, pp. 237-244, 2008, DOI:10.3970/fdmp.2008.004.237

Abstract The transient thermal behavior of a two-dimensional circulating porous bed is analytically investigated. A one-energy equation model, representing both the gas and solid phases via a unified temperature, is employed to describe the thermal behavior of the circulating bed. The latter is essentially a tube and shell heat exchanger commonly used in technologically important applications. The model equation is transformed into a simpler set of partial differential equations using an analytical procedure. The analytical solution, based on the method of separation of variables and the principle of superposition, is formulated for the calculation of the temperature distribution in the radial… More >

V.G. Kozlov¹, N.V. Selin²

FDMP-Fluid Dynamics & Materials Processing, Vol.2, No.2, pp. 107-118, 2006, DOI:10.3970/fdmp.2006.002.107

Abstract Thermal vibrational convection in a sector of a thin spherical liquid layer subjected to pendulum vibrations (spherical pendulum) is investigated theoretically and experimentally. Temperature non-uniformity inside the liquid is caused by uniformly distributed internal heat sources (one side of the layer is isothermal, the other one is adiabatic). Experiments are carried out under conditions of stable temperature stratification in the gravity field. Heat transfer and convective structure are investigated in a wide interval of governing dimensionless parameters. A critical increase of heat transfer is revealed as the vibrations intensity is increased, caused by average convection. It is shown that thermal… 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 >