Open Access
ARTICLE
H. Azoui1, D. Bahloul1,*, N. Soltani2
FDMP-Fluid Dynamics & Materials Processing, Vol.14, No.2, pp. 87-105, 2018, DOI: 10.3970/fdmp.2018.01149
Abstract In this work we have performed a three-dimensional numerical investigation in order to find the optimal conditions for growing efficiently high quality sapphire crystals with good thermal properties. We have studied thermal instabilities near the melt-crystal interface and the convective heat transfer under the Czochralski (Cz) process. We performed 3-D CFD simulation in cylindrical coordinates and used the Fast Fourier Transform method to analyze the temperature fluctuations. We present a detailed investigation on the effects of the crystal rotation speed and the temperature distribution on thermal instabilities of sapphire melt under forced convection. Where the melt forced convection, the radiative… More >
Open Access
ARTICLE
Fatiha Bentarzi1, Amina Mataoui1, *
FDMP-Fluid Dynamics & Materials Processing, Vol.14, No.2, pp. 107-120, 2018, DOI: 10.3970/fdmp.2018.06046
Abstract The dynamics of two fully developed turbulent jets, perpendicular to a heated flat plate and related heat transfer mechanism are analysed numerically. This problem is relevant to several thermal engineering applications. The governing equations are solved by a finite volume method with a second order RSM model combined with wall functions used for turbulent modelling. The possibility to improve heat transfer is assessed taking into account the characteristic parameters for the jet-wall interaction. In particular, a parametric study is conducted by varying the jet Reynolds number (Re) and the nozzle to plate distance (D). The distance between the two jets… More >
Open Access
ARTICLE
Nouri Sabrina1,*, Abderrahmane Ghezal1, Said Abboudi2, Pierre Spiteri3
FDMP-Fluid Dynamics & Materials Processing, Vol.14, No.2, pp. 121-135, 2018, DOI: 10.3970/fdmp.2018.02045
Abstract This paper deals with the numerical study of heat and mass transfer occurring in a cavity filled with a low Prandtl number liquid. The model includes the momentum, energy and mass balance equations. These equations are discretized by a finite volume technique and solved in the framework of a custom SIMPLER method developed in FORTRAN. The effect of the problem characteristic parameters, namely the Lewis and Prandtl numbers, on the instability of the flow and related solute distribution is studied for positive and negative thermal and solutal buoyancy forces ratio. Nusselt and Sherwood numbers are derived for values of the… More >
Open Access
ARTICLE
A. Khechiba1, Y. Benakcha1, A. Ghezal1, P. Spetiri2
FDMP-Fluid Dynamics & Materials Processing, Vol.14, No.2, pp. 137-154, 2018, DOI: 10.3970/fdmp.2018.04054
Abstract This work investigates the dynamic behavior of a pulsatile flow electrically conducting through porous medium in a cylindrical conduit under the influence of a magnetic field. The imposed magnetic field is assumed to be uniform and constant. An exact solution of the equations governing magneto hydro-dynamics (MHD) flow in a conduit has been obtained in the form of Bessel functions. The analytical study has been used to establish an expression between the Hartmann number, Darcy number and the stress coefficient. The numerical method is based on an implicit finite difference time marching scheme using the Thomas algorithm and Gauss Seidel… More >