3D Analysis of Crystal/Melt Interface Shape and Marangoni Flow Instability in Solidifying Liquid Bridges

Abstract

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Three-dimensional numerical simulation of Marangoni flow instabilities in floating zones laterally heated by an equatorial ring

“…The concentration distribution, however, was found to be azimuthally distorted from a ''macroscopic'' point of view. The numerical results 19 have confirmed that the steady bifurcation of Marangoni flow can affect the crystallization process.…”

“…This was proved from an experimental point of view by Camel et al 18 and confirmed by the numerical simulations of Lappa and Savino. 19 ''Weak laminar nonaxisymmetric convection'' in the liquid phase may induce radial segregation with a nonaxisymmetric distribution. 18 Experiments showing these behaviors were carried out during the German Spacelab Mission D-2.…”

Analysis of flow instabilities in convex and concave floating zones heated by an equatorial ring under microgravity conditions

“…Nevertheless, as demonstrated from an experimental point of view by Camel et al [19] and confirmed by the numerical simulations of Lappa and Savino [20], also this instability can play a ''critical role'' in the crystallization process (the steady bifurcation of Marangoni flow in fact can be responsible for the azimuthal distortion of the melt/crystal interface at macroscopic length scale).…”

Thermal convection and related instabilities in models of crystal growth from the melt on earth and in microgravity: Past history and current status

“…The free interface was assumed to be cylindrical in these studies and the azimuthal wave number (m) was found to behave as a decreasing function of the aspect ratio i.e. 2mA=const; Lappa and Savino [67] extended such a relationship to the case of dynamical aspect ratio changes induced by solidification. Imaishi et al [68] depicted in detail the complex spatio-temporal evolution of the flow field that occurs after the secondary (oscillatory) bifurcation of the Marangoni flow for different values of the aspect ratio A and of the Prandtl number (0≤Pr≤0.02), elucidating different (referred to as "torsional") oscillatory behaviours (Fig.…”