B. Madani¹, F. Topin², L. Tadrist²

FDMP-Fluid Dynamics & Materials Processing, Vol.6, No.4, pp. 351-368, 2010, DOI:10.3970/fdmp.2010.006.351

Abstract The present work deals with the hydraulic characterization of two-phase flow with phase change in a channel filled with metallic foam. We provide a general presentation of metallic foams including morphological characteristics, fabrication processes and industrial applications. The experimental facility, which consists of a hydrodynamic loop, the test section, measurement devices, and the data acquisition system, is presented. The Metallic foam sample tested in the present work is manufactured by SCPS (French manufacturer). N-pentane is used as a coolant fluid. The mass velocity values lie between 4 and 49 kg/ m2s, while the heating power More >

R.C. Bataller¹

FDMP-Fluid Dynamics & Materials Processing, Vol.6, No.3, pp. 337-350, 2010, DOI:10.3970/fdmp.2010.006.337

Abstract The present research gathers an accurate numerical study of the laminar flow induced in an incompressible upper-convected Maxwell (UCM) fluid by a linear stretching of a flat, horizontal and porous sheet in the presence of a transverse magnetic field. The governing partial differential equations are converted into an ordinary differential equation by a similarity transformation. The effects on the velocity field over the sheet of the parameters like elasticity number, suction/blowing velocity, and magnetic parameter are also studied. It has also been attempted to show capabilities and wide-range applications of the 4thorder Runge-Kutta method in More >

G. P. Russo¹, A. Esposito¹, B. Esposito², R. Renis^1,1, F. Parente¹

FDMP-Fluid Dynamics & Materials Processing, Vol.6, No.3, pp. 319-336, 2010, DOI:10.3970/fdmp.2010.006.319

Abstract A low-cost facility, able to simulate icing conditions occurring in flight, has been built via modification of a small blow-down supersonic wind tunnel. As the storage tank (30bar) is emptied through the wind tunnel, expansion of the contained air makes temperature to decrease down to -20 C and a control valve holds such temperature for about 200s. In order to increase the liquid water content (LWC) of the flow allowing ice formation on model surfaces within the test chamber, water is sprayed in the stream within the stagnation chamber by means of a controlled spray… More >

Nedeltcho K,ev¹, Val Kagan², Ahmed Daoud¹

FDMP-Fluid Dynamics & Materials Processing, Vol.6, No.3, pp. 291-318, 2010, DOI:10.3970/fdmp.2010.006.291

Abstract Results are presented of 3D numerical magneto-hydrodynamic (MHD) simulation of electromagnetic DC pump for both laminar and turbulent metal flow under an externally imposed strongly non-uniform magnetic field. Numerous MHD flow cases were simulated using finite element method and the results of five typical examples are summarized here, including one example of laminar brake flow, one example of turbulent brake flow and three examples of turbulent pumping conditions. These simulations of laminar and turbulent channel flow of liquid metal correctly represent the formation of an M shaped velocity profile and are in good agreement with… More >

R. M. Patel¹, G. M. Deheri², P. A. Vadher³

FDMP-Fluid Dynamics & Materials Processing, Vol.6, No.3, pp. 277-290, 2010, DOI:10.3970/fdmp.2010.006.277

Abstract An endeavor has been made to analyze the performance of an infinitely long magnetic fluid based hydrodynamic slider bearing in the presence of a magnetic fluid lubricant. The associated Reynolds' equation is solved with appropriate boundary conditions. Expressions for dimensionless pressure, load carrying capacity and friction are obtained. Computed values are displayed graphically. It is seen that the magnetic fluid lubricant improves the performance of the bearing system. The friction decreases at the moving plate while it increases nominally at the fixed plate due to magnetization. In order to extend the life period of this More >

S. Bouabdallah^1,2, R. Bessaïh¹

FDMP-Fluid Dynamics & Materials Processing, Vol.6, No.3, pp. 251-276, 2010, DOI:10.3970/fdmp.2010.006.251

Abstract In this paper, a numerical study of magnetohydrodynamics stability during phase change of a pure metal (liquid Gallium) in a cubical enclosure is presented. An external magnetic field is applied in X-, Y-, and Z-directions separately. Two electric potential boundary conditions are considered: electrically conducting and insulating walls. The finite-volume method with enthalpy formulation is used to solve the mathematical model in the solid and liquid phases. The Grashof number is fixed at Gr =105and the Hartmann number is varied from Ha= 0 to 200. The effect of magnetic field on the flow field and More >

E. A. Semma¹, M. El Ganaoui², V. Timchenko³, E. Leonardi³

FDMP-Fluid Dynamics & Materials Processing, Vol.6, No.3, pp. 233-250, 2010, DOI:10.3970/fdmp.2010.006.233

Abstract The effects of oscillatory heating on thermosolutal convection in a cavity heated from below are investigated and discussed. The transient Navier-Stokes equations coupled with heat and mass balances are solved numerically by using a control-volume technique. It is assumed that the interface moves with constant growth velocity. The results show the presence of multiple solutions in response to simultaneous vertical temperature and species concentration gradients applied to the system. In particular, two critical frequencies are identified, one corresponding to low values of the buoyancy ratio N (N~1), accompanied with a decrease of flow intensity reaching More >

Shadia J Ikhmayies¹, Naseem M. Abu El-Haija², Riyad N. Ahmad-Bitar³

FDMP-Fluid Dynamics & Materials Processing, Vol.6, No.2, pp. 219-232, 2010, DOI:10.3970/fdmp.2010.006.219

Abstract Large area and highly uniform polycrystalline ZnO thin films have been produced by a spray pyrolysis (SP) technique resorting to a customized system (spraying) on glass substrates at temperature Ts= 450℃. This study deals with the related investigation about the influence of heat treatment (in nitrogen atmosphere) on the resulting properties (electrical, optical and structural) of such films. Properties are analyzed by means of I-V plots, transmittance curves, X-Ray diffractograms (XRD) and scanning electron microscope (SEM) micrographs. Results show that the resistivity of the films decreases from about 200W.cm for the as-deposited films to about… More >

A. Benaissa¹, I. Yimer²

FDMP-Fluid Dynamics & Materials Processing, Vol.6, No.2, pp. 203-218, 2010, DOI:10.3970/fdmp.2010.006.203

Abstract This work presents a study on the effect of pulsing on a jet flow. Pulsing is used to modify jet inlet conditions with the objective of improving mixing. In this experimental work, a jet was slightly heated so that temperature could be considered as a passive scalar. The spectral behaviour of velocity and the passive scalar temperature was analyzed along the jet axis with and without pulsing. Low frequency pulsing (f/fS< 0.05 fSthe Strouhal frequency) modifies the spectral composition of the velocity at the jet exit, but it does not affect the asymptotic profile reached… More >

Leela Rakesh¹, Anja Mueller², Pratik Chhetri¹

FDMP-Fluid Dynamics & Materials Processing, Vol.6, No.2, pp. 179-202, 2010, DOI:10.3970/fdmp.2010.006.179

Abstract A new material for proton conducting membrane with a higher proton transport but reduced water transport is being developed. The new material optimizes proton channel formation, this reducing water transport at the same time. Different proton transporting groups along with different gas flowing channels are examined as well. To meet the goals we design, synthesize, and simulate various proton transporting groups using MD techniques for faster optimization, which in turn helps to synthesize and test only promising structures in the laboratory. At the same time, computer modeling is used to improve the fuel cell system More >