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M. Sekhon¹, N. Armour¹, S. Dost^1,2
FDMP-Fluid Dynamics & Materials Processing, Vol.9, No.4, pp. 331-351, 2013, DOI:10.3970/fdmp.2013.009.331
Abstract Liquid Phase Diffusion (LPD) growth of Si_xGe_1-x single crystals has been numerically simulated under zero gravity. The objective was to examine growth rate and silicon concentration distribution in the LPD grown crystals under diffusion dominated mass transport prior to the planned LPD space experiments on the International Space Station (ISS). Since we are interested in predicting growth rate and crystal composition, the gravitational fluctuation of the ISS (g-jitter) was neglected and the gravity level was taken as zero for simplicity.
A fixed grid approach has been utilized for the simulation. An integrated top-level solver was developed in OpenFOAM to carry… More >

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ARTICLE

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 >

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ARTICLE

Payam Sharifi¹, Asghar Esmaeeli²
FDMP-Fluid Dynamics & Materials Processing, Vol.9, No.4, pp. 389-418, 2013, DOI:10.3970/fdmp.2013.009.389
Abstract This study aims to explore the effect of liquid film thickness on the electrohydrodynamic-driven instability of the interface separating two horizontal immiscible liquid layers. The fluids are confined between two electrodes and the light and less conducting liquid is overlaid on the heavy and more conducting one. Direct Numerical Simulations (DNSs) are performed using a front tracking/finite difference scheme in conjunction with Taylor-Melcher leaky dielectric model. For the range of physical parameters used here, it is shown that for a moderately thick lower liquid layer, the interface instability leads to formation of several liquid columns and as a result of… More >

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1047

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J.R. Lin¹, P.J. Li², T.C. Hung³
FDMP-Fluid Dynamics & Materials Processing, Vol.9, No.4, pp. 419-434, 2013, DOI:10.3970/fdmp.2013.009.419
Abstract On the basis of the Shliomis ferrofluid model (1972) together with the micro-continuum theory of Stokes (1966), the influences of non-Newtonian ferrofluids on the steady-state performance of long journal bearings have been investigated in the present paper. Analytical solutions for bearing performances are obtained from the non-Newtonian ferrofluid Reynolds-type equation. Comparing with the Newtonian non-ferrofluid case, the effects of non-Newtonian ferrofluids with applied magnetic fields provide an increase in the zero pressure-gradient angle and the load capacity, and a decrease in the friction parameter, especially for a larger non-Newtonian couple stress parameter and magnetic Langevin’s parameter. For the long journal… More >

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1118

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Md. Abdul Halim¹, Asghar Esmaeeli²
FDMP-Fluid Dynamics & Materials Processing, Vol.9, No.4, pp. 435-460, 2013, DOI:10.3970/fdmp.2013.009.435
Abstract This study aims to gain a detailed understanding of the transient behavior of solitary liquid drops in electric fields at finite Reynolds number. A front tracking/finite difference method, in conjunction with Taylor-Melcher leaky dielectric model, is used to solve the governing electrohydrodynamic equations. The evolution of the flow field and drop deformation is studied for a few representative fluid systems, corresponding to the different regions of the deformation-circulation map. It is shown that for the range of the physical parameters used here, the deformationtime history is governed by one time scale while the fluid flow (characterized by kinetic energy) is… More >

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1333

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V. Carandente¹, R. Savino¹, M. Iacovazzo¹, C. Boffa
FDMP-Fluid Dynamics & Materials Processing, Vol.9, No.4, pp. 461-484, 2013, DOI:10.3970/fdmp.2013.009.461
Abstract The article deals with the aerothermal analysis of a sample-return hypersonic capsule reentering on Earth from an interplanetary exploration mission. The main objective of the work is to estimate the heat flux distribution on the capsule surface and to perform one-dimensional thermal analyses for its ablative heat shield. After a short review of sample-return missions, the numerical models implemented are described and the computational results, obtained along a feasible reentry trajectory, are presented and discussed. Particular attention has been paid to compare the convective stagnation point heat fluxes obtained by means of Computational Fluid Dynamic (CFD) analyses with the ones… More >

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