M. Dandani^1,*, V. Lepiller², A. Ghezal³, P. Desevaux⁴

FDMP-Fluid Dynamics & Materials Processing, Vol.14, No.1, pp. 23-37, 2018, DOI:10.3970/fdmp.2018.014.023

Abstract The present study deals with the numerical visualization of the mixing process in a 2D supersonic ejector. The mixing process is visualized using two CFD flow visualization methods. The first method consists in introducing discrete particles in the secondary flow and computing their trajectories. The second method consists in modeling the diffusion of a passive scalar introduced in one of the two flows. The mixing process is investigated in the case of a conventional 2D supersonic ejector and a second case of an ejector equipped with transverse micro jets. Flow visualizations obtained show the existence of a significant mixing enhancement… More >

Mustapha FARAJI¹

FDMP-Fluid Dynamics & Materials Processing, Vol.13, No.1, pp. 19-36, 2017, DOI:10.3970/fdmp.2017.013.019

Abstract A two-dimensional numerical model that accounts for heat transfer by conduction and natural convection in the molten region of nano enhanced Phase Change Material (PCM) is performed. Numerical investigations were conducted using an enthalpy- porosity method in order to examine the impact of the dispersion of copper (CuO) nanoparticles on the heat source temperature and the effect on the heat sink secured working time and the melting rate. Results show that heat spreads more easily along the conducting plate and to the PCM and, consequently, the PCM melts rapidly and the heat source is efficiency cooled by the addition of… More >

N. Soltani¹, S. Rahal¹

FDMP-Fluid Dynamics & Materials Processing, Vol.13, No.1, pp. 1-17, 2017, DOI:10.3970/fdmp.2017.013.001

Abstract A three-dimensional time-dependent numerical study of the flow instabilities in a simulated Czochralski system is conducted. The comparison with previously published experimental results is reported. The simulations were performed using a refined grid in order to investigate flow instabilities in the crucible. Simulations have been carried out for various crystal rotational speeds, by taking into account the effects of Rayleigh and Marangoni numbers. The temperature fluctuations near the crystal/liquid interface are analyzed. The method used for that purpose is the Fast Fourier Transform with the corresponding spectra. From numerical simulations, it has been observed that for rotational speeds of the… More >

Rodica Borcia¹, Michael Bestehorn²

FDMP-Fluid Dynamics & Materials Processing, Vol.6, No.1, pp. 1-12, 2010, DOI:10.3970/fdmp.2010.006.001

Abstract We study numerically the fully nonlinear evolution of thin liquid films on solid supports in three spatial dimensions. A phase field model is used as mathematical tool. Homogeneous and inhomogeneous substrates are taken into account. For flat homogeneous substrates the stability of thin liquid layers is investigated under the action of gravity. The coarsening process at the solid boundary can be controlled on inhomogeneous substrates. On substrates chemically patterned in an adequate way with hydrophobic and hydrophilic spots (functional surfaces), one can obtain stable regular liquid droplets as final dewetted morphology. 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 >

A. Saad^1,2, A. Echchelh¹, M. Hattabi³, M. El Ganaoui⁴, F. Lahlou¹

FDMP-Fluid Dynamics & Materials Processing, Vol.8, No.3, pp. 277-294, 2012, DOI:10.3970/fdmp.2012.008.277

Abstract A modified finite element/control volume (FE/CV) method is used to solve the resin flow problem. Full advantage is taken of some of the intrinsic peculiar characteristics of the method, in particular, of its capability of eliminating the need to remesh continuously the resin-filled domain at each time step. The model leads to the numerical prediction of temperature, pressure distribution and flow front position with great accuracy, together with a precise representation of the thermal (spatio-temporal) behaviour of the resin inside the mould. The validity of such approach is validated by comparison with available analytical results. Results demonstrate that this modified… More >

C. Giessler¹, C. Sievert², U. Krieger¹, B. Halbedel¹, D. Huelsenberg¹, U. Luedke², A. Thess^1,2,3

FDMP-Fluid Dynamics & Materials Processing, Vol.1, No.3, pp. 247-266, 2005, DOI:10.3970/fdmp.2005.001.247

Abstract Buoyancy driven motion of a highly viscous electrically conducting fluid under the influence of Lorentz forces is investigated theoretically and experimentally. This problem is relevant to the processing of glass, where it is of considerable interest to know whether electromagnetic forces can effectively improve mixing and help to avoid undesired flow patterns in glass melting furnaces. Two highly simplified models are proposed in which the fluid is assumed to be confined in a circular loop containing several localized resistive heating, convective cooling, and electromagnetic forcing elements. The first model is used to derive the scaling laws of the mean velocity… More >

Marcello Lappa¹

FDMP-Fluid Dynamics & Materials Processing, Vol.1, No.2, pp. 171-188, 2005, DOI:10.3970/fdmp.2005.001.171

Abstract The paper presents a comparative and critical analysis of some theoretical/experimental/numerical arguments concerning the possible stabilization of the surface-tension-driven (Marangoni) flow in the Floating Zone technique and in various related fluid-dynamic models. It is conceived as a natural extension of the focused overview published in Cryst. Res. Tech. 40(6), 531, (2005) where much room was devoted to discuss the intrinsic physical mechanisms responsible for three-dimensional and oscillatory flows in a variety of technological processes. Here, a significant effort is provided to illustrate the genesis of possible control strategies (many of which are still in a very embryonic condition), the underlying… More >

Gustav Amberg¹, Junichiro Shiomi²

FDMP-Fluid Dynamics & Materials Processing, Vol.1, No.1, pp. 81-96, 2005, DOI:10.3970/fdmp.2005.001.081

Abstract A few issues in materials science are reviewed with regard to the importance of fluid flows. The effect of convection on generic solidification problems is discussed. One relevant class of flows in melts is those driven by surface tension gradients. In welding this thermo- or solutocapillary flow will determine the penetration depth, and will depend very sensitively on the composition of the material, through the dependence of surface tension on temperature, presence of surfactants, etc. In crystal growth the convective motion in the melt may cause instabilities that are often undesired in practical processes. The unsteady flow structure can cause… More >

Priyankar Datta¹, Manas C. Ray¹

CMC-Computers, Materials & Continua, Vol.49-50, No.1, pp. 47-80, 2015, DOI:10.3970/cmc.2015.049.047

Abstract This paper deals with the implementation of the one dimensional form of the fractional order derivative constitutive relation for three dimensional analysis of active constrained layer damping (ACLD) of geometrically nonlinear laminated composite plates. The constraining layer of the ACLD treatment is composed of the vertically/obliquely reinforced 1–3 piezoelectric composites (PZCs). The von Kármán type nonlinear strain displacement relations are used to account for the geometric nonlinearity of the plates. A nonlinear smart finite element model (FEM) has been developed. Thin laminated substrate composite plates with various boundary conditions and stacking sequences are analyzed to verify the effectiveness of the… More >