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Pravin Subramanian¹, Abdelfattah Zebib¹
FDMP-Fluid Dynamics & Materials Processing, Vol.4, No.3, pp. 139-162, 2008, DOI:10.3970/fdmp.2008.004.139
Abstract A theoretical and computational study of solutocapillary driven Marangoni instabilities in small spherical shells is presented. The shells contain a binary fluid with an evaporating solvent. The viscosity is a strong function of the solvent concentration, the inner surface of the shell is assumed impermeable and stress free, while non-linear boundary conditions are modeled and prescribed at the receding outer boundary. A time-dependent diffusive state is possible and may lose stability through the Marangoni mechanism due to surface tension dependence on solvent concentration (buoyant forces are negligible in this micro-scale problem). The Capillary number (Ca) provides a measure of the… More >

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ARTICLE

Sayavur I. Bakhtiyarov¹, Dennis A. Siginer²
FDMP-Fluid Dynamics & Materials Processing, Vol.4, No.3, pp. 163-184, 2008, DOI:10.3970/fdmp.2008.004.163
Abstract This article has no abstract. More >

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821

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ARTICLE

A. A. Nepomnyashchy^1,2, I. B. Simanovskii¹
FDMP-Fluid Dynamics & Materials Processing, Vol.4, No.3, pp. 185-198, 2008, DOI:10.3970/fdmp.2008.004.185
Abstract The development of instabilities under the joint action of the van der Waals forces and Marangoni stresses in a two-layer film on a heated or cooled substrate is considered. It is found that heating from below leads to the acceleration of the decomposition, decrease of the characteristic lateral size of structures, and the increase of the droplets heights. Heating from above leads to slowing down the instability rate and eventually to a complete suppression of the instability. More >

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888

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ARTICLE

K. Achoubir¹, R. Bennacer², A. Cheddadi¹, M. El Ganaoui³, E. Semma^3,4
FDMP-Fluid Dynamics & Materials Processing, Vol.4, No.3, pp. 199-210, 2008, DOI:10.3970/fdmp.2008.004.199
Abstract The present work is devoted to the numerical investigation of the interaction between thermal and solutal convection in enclosures used for modeling directional solidification. The full transient Navier--Stokes, energy and species conservation equations are solved numerically by using finite volumes technique. More >

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723

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A.A. Ivanova¹, V.G. Kozlov^1,2,3, D.A. Polezhaev¹, D. Pareau³, M. Stambouli³
FDMP-Fluid Dynamics & Materials Processing, Vol.4, No.3, pp. 211-220, 2008, DOI:10.3970/fdmp.2008.004.211
Abstract The problem for the optimization of mass-transfer on the interface of two immiscible liquids by means of vibrational hydromechanics is studied experimentally. A new vibrational cell of Lewis's type expressly conceived for such purposes is described. Flow is generated by activators in the form of disks inducing translational axial oscillations near the opposite end faces of the cavity. It is shown that such vibrating disks can lead to the onset of a large-scale toroidal whirlwind effectively mixing the liquid throughout the volume. According to the experiments, in particular, axisymmetrical radial flows are generated on both sides of the horizontal liquid… More >

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