C. S. Iorio¹, C. Perfetti¹

FDMP-Fluid Dynamics & Materials Processing, Vol.11, No.1, pp. 27-48, 2015, DOI:10.3970/fdmp.2015.011.027

Abstract In the past few years, modeling of the Acoustic StandingWaves (ASW) phenomena has become a topic of great interest due to its theoretical connections with particle/cells manipulation techniques, which represent important tools in the biotechnology field. The present paper proposes a model based on the use of moving wall boundary conditions coupled with a viscous compressible fluid in a square channel. This model successfully achieved the generation of ASWs in the square cross-section for several resonance frequencies; the corresponding acoustic potential for the fundamental resonant mode and several harmonics have also been calculated and are discussed here. More >

Robert Rundqvist¹, Andreas Mark¹, Fredrik Edelvik¹, Johan S. Carlsson¹

FDMP-Fluid Dynamics & Materials Processing, Vol.7, No.3, pp. 259-278, 2011, DOI:10.3970/fdmp.2011.007.259

Abstract Multiphase flow simulation using Smoothed Particle Hydrodynamics (SPH) has gained interest during recent years, mostly due to the inherent flexibility of the method and the physically rather intuitive formulation of extra constitutive equations needed when dealing with for instance non-Newtonian flows. In the work presented here, simulations based on an SPH model implemented in the flow solver IBOFlow has been used for simulation of robotic application of sealing material on a car body. Application of sealing materials is done in order to prevent water leakage into cavities of the body, and to reduce noise. In off-line programming of the robots… More >

S. Hamimid¹, A.Amroune¹

FDMP-Fluid Dynamics & Materials Processing, Vol.6, No.4, pp. 369-384, 2010, DOI:10.3970/fdmp.2010.006.369

Abstract The Navier-Stokes and energy equations are numerically solved to investigate two-dimensional convection (originating from the combined effect of buoyancy and surface tension forces) in a liquid metal subjected to transverse magnetic fields. In particular, a laterally heated horizontal cavity with aspect ratio (height/width) =1 and Pr=0.015 is considered (typically associated with the horizontal Bridgman crystal growth process and commonly used for benchmarking purposes). The effect of a uniform magnetic field with different magnitudes and orientations on the stability of the two distinct convective solution branches (with a single-cell or two-cell pattern) of the steady-state flows is investigated. The effects induced… 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 at various operating conditions, specifically… More >

A. Alke¹, D. Bothe¹

FDMP-Fluid Dynamics & Materials Processing, Vol.5, No.4, pp. 345-372, 2009, DOI:10.3970/fdmp.2009.005.345

Abstract We present a computational approach based on the Volume-of-Fluid (VOF) method for simulating the influence of a soluble surfactant on the behavior of two-phase systems with deformable interface. Our approach is applicable to diffusion controlled processes, where the relation between the area-specific excess surfactant concentration on the interface and the volume-specific concentration adjacent to the interface is given by an adsorption isotherm. Main issues of the numerical model are an extended surface transport theorem used for describing the interfacial flux and an iso-surface of the VOF-variable used as a connected approximation for the interface. 3D-simulations of a bubble moving through… 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 convection but also generated an… More >

C.P. Hong¹, M.F. Zhu², S.Y. Lee¹

FDMP-Fluid Dynamics & Materials Processing, Vol.2, No.4, pp. 247-260, 2006, DOI:10.3970/fdmp.2006.002.247

Abstract In typical solidification processes the flow of molten metal is usually regarded as an unavoidable phenomenon potentially affecting the morphology of dendritic growth. Fundamental understanding of such flow is thus important for predicting and controlling solidification microstructures. This paper presents numerical simulations on the evolution of dendritic microstructures with melt convection. A two-dimensional modified cellular automaton (MCA) coupled with a transport model is developed to simulate solidification of binary and ternary alloys in the presence of fluid flow. This model takes into account the effects of the constitutional undercooling and curvature undercooling on the equilibrium interface temperature. It also considers… More >

M. Sohail¹, M. Z. Saghir¹

FDMP-Fluid Dynamics & Materials Processing, Vol.2, No.2, pp. 127-140, 2006, DOI:10.3970/fdmp.2006.002.127

Abstract A numerical simulation study is carried out for the crystal growth of Ge1-xSixby the Traveling Heater Method (THM). The effects of a geometrical misalignment on the crystal growth are investigated. The full Navier-Stokes equations together with the energy, mass transport and continuity equations are solved numerically using the finite element technique. The application of a misalignment is shown to have a considerable effect on the buoyancy induced flow. An optimal misalignment is determined, that weakens the convective flow, provides a uniform concentration along the growth interface and gives symmetrical characteristics to the three-dimensional buoyancy induced flow. More >

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 >

A. Belcaid^1,2, G. Le Palec², A. Draoui¹, Ph. Bournot¹

FDMP-Fluid Dynamics & Materials Processing, Vol.8, No.2, pp. 241-256, 2012, DOI:10.3970/fdmp.2012.008.241

Abstract The study is focused on numerical simulation of the process of coastal pollution by wastewater in the Bay of Tangier in Morocco. The process is governed by flows generated by the tide and the large variations of the discharges from the different Wadis (rivers) flowing into the bay. The simulation requires a number of tests and trials, something that is experimentally expensive and sometimes impossible. Hence the idea was developed of a numerical study aimed at tracking the dispersion of pollutants into the bay and determining the level of degradation of its waters. The simulation was done using the computer… More >