Shishir Sinha¹, Vinay Kumar²

FDMP-Fluid Dynamics & Materials Processing, Vol.5, No.3, pp. 297-312, 2009, DOI:10.3970/fdmp.2009.005.297

Abstract High-capacity ion exchange resins based on Poly Methyl Methacrylate (PMMA) was developed during this study having higher mechanical strength, stable and, hydrophilic in nature compared to Poly styrene (PS) based systems. PMMA was cross-linked by Di Vinyl Benzene (DVB) to get macro porous PMMA-DVB resins by suspension polymerization. PMMA-DVB resins were surface modified by nitration followed by amination under appropriate temperature conditions. Change in the color of resin from white to pale yellow and pale yellow to golden yellow as well as characteristic peaks of NO2at 700 cm-1and 1400 cm-1and 3100-3200 cm-1for NH2group in FTIR 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 More >

R. Djebali^1,2, M. El Ganaoui^2,3, H. Sammouda¹, R. Bennacer⁴

FDMP-Fluid Dynamics & Materials Processing, Vol.5, No.3, pp. 261-282, 2009, DOI:10.3970/fdmp.2009.005.261

Abstract The simplified thermal lattice Boltzmann model (STLBM) developed by Peng, Shu and Chew (2003) is used in this work to simulate low-Rayleigh-number natural convection in a heated rectangular cavity on a uniform grid. It is shown how by resorting to the double populations approach both hydrodynamic and thermal fields can be effectively simulated. Furthermore, a general benchmark is carried out to account for the effect of different parameters in relatively wide ranges. Results are compared with previous works available in the literature. More >

Nikhilkumar D. Abhangi¹, G. M. Deheri¹

FDMP-Fluid Dynamics & Materials Processing, Vol.5, No.3, pp. 245-260, 2009, DOI:10.3970/fdmp.2009.005.245

Abstract Efforts have been directed to study and analyze the behavior of a magnetic-fluid-based squeeze film between curved rough circular plates when the curved upper plate (with surface determined by an exponential expression) approaches the stationary curved lower plate (with surface governed by a secant function). A magnetic fluid is used as the lubricant in the presence of an external magnetic field oblique to the radial axis. The bearing surfaces are assumed to be transversely rough and the related roughness is characterized via a stochastic random variable with non-zero mean variance and skewness. The associated Reynolds… More >

J. Roszmann¹, Y.C. Liu¹, S. Dost^1,2, B. Lent¹, S. Grenier³, N. Audet³

FDMP-Fluid Dynamics & Materials Processing, Vol.5, No.3, pp. 231-244, 2009, DOI:10.3970/fdmp.2009.005.231

Abstract The article presents the results of a combined numerical and experimental study of the effect of rotating magnetic field on impurity transport in a zone refining system. An impurity (selenium) with a segregation coefficient close to unity was targeted. The three-zone system previously developed was used for experiments and numerical simulations. The numerical simulations were performed for tellurium (Te) and cadmium (Cd) molten zones, but the experiments could only be carried out for the Te-system. More >

M.M. Shemirani¹, M.Z. Saghir²

FDMP-Fluid Dynamics & Materials Processing, Vol.5, No.3, pp. 211-230, 2009, DOI:10.3970/fdmp.2009.005.211

Abstract A three-dimensional numerical modeling of Ge0.98Si0.02crystal growth is conducted to investigate the effect of g-jitter along with rotating magnetic field on the heat and mass transfer in the solvent region. It was found that the speed in the flow under the low frequency g-jitter is in the nano-centimeter per second and is too weak to have any impact on the silicon concentration in the process of crystallization near the growth interface. Different magnetic field intensities for different rotational speeds were examined. It was also found that rotating magnetic field not only did not suppress the More >

R. Abdeljabar¹

FDMP-Fluid Dynamics & Materials Processing, Vol.5, No.2, pp. 193-210, 2009, DOI:10.3970/fdmp.2009.005.193

Abstract A theoretical model has been developed to predict the expansion of a salty gradient (i.e. the interface) layer under natural diffusion. The salty gradient layer is initially sandwiched between two homogeneous miscible layers of varying salinity, which may or may not have the same thickness. The model describes the concentration profile of the salty gradient layer (expressed by analytical solutions of the diffusion equation) as the boundaries of this interfacial layer move into the adjacent (hitherto homogeneous) regions. The lifetime of the adjacent layers is also predicted. An experimental study for a configuration with salty More >

L. Bennamoun¹, A. Belhamri², A. Ali Mohamed

FDMP-Fluid Dynamics & Materials Processing, Vol.5, No.2, pp. 177-192, 2009, DOI:10.3970/fdmp.2009.005.177

Abstract This study focuses on the interplay between drying kinetics (encountered in typical industrial processes and particularly in the context of solar drying) and the possible variation of external (e.g., environmental) conditions. Theoretical models of these behaviours are introduced. Experimental results confirmed by simulation are also presented. Variation of the thermo physical properties of air is taken into account in terms of variation of viscosity, density and coefficient of diffusion. In particular, this coefficient is calculated from experimental data and expressed as a function of the wet bulb air temperature. When external conditions are modified and,… More >

M.R. Arab^1,2, E. Semma³, B. Pateyron¹, M. El Ganaoui¹

FDMP-Fluid Dynamics & Materials Processing, Vol.5, No.2, pp. 161-176, 2009, DOI:10.3970/fdmp.2009.005.161

Abstract In this work, flows in porous media are simulated by using a Lattice Boltzmann Method (LBM). A model D2Q9 with a single collision operator is proposed. This method is applied on 2D digital images obtained by a Scanning Electron Microscope technique (SEM), and followed by a special treatment in order to obtain an image of synthesis that is finally read by the numerical code. The first results tested on two-dimensional configurations show the reliability of this strategy in simulating with a good accuracy phenomena of heat and mass transport. The numerical study is extended to More >

Norihan M. Arifin¹, Ioan Pop²

FDMP-Fluid Dynamics & Materials Processing, Vol.5, No.2, pp. 149-160, 2009, DOI:10.3970/fdmp.2009.005.149

Abstract A linear stability analysis is used to investigate the onset of Marangoni convection in a three-layer system comprising an incompressible fluid saturated porous layer over which lies a layer of the same fluid and below which lies a solid layer. The lower boundary is subjected to a fixed heat flux, while the upper free surface of the fluid is non-deformable. At the interface between the fluid and the porous layer, the Beavers-Joseph slip condition is used and the Darcy law is employed to describe the flow in the porous medium. The asymptotic analysis of the More >