New features in the fluid-dynamics of floating zones under Marangoni effect

Marcello Lappa, Raffaele Savino

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Abstract

The article presents a discussion of the floating-zone (FZ) problem and of the
related three-dimensional flow instability in terms of numerical simulations and
prototype applications. The difference between the "half-zone" and the "fullzone" and the related possibility to use one or the other configuration to capture the FZ fundamental hydrodynamics are elucidated. The first bifurcation of the flow is investigated in the case of semiconductor melts for various environments (microgravity and normal gravity) and geometrical parameters (wide ranges of aspect ratio and volume). In the case of Silicon the axi-symmetric flow loses its stability to a steady three-dimensional flow. The model (half or full column) used for the simulations, however, plays a critical role in determining the related azimuthal structure and critical threshold. For Pr=0.02 (Gallium) and on-ground conditions, a surprising behaviour is observed. The flow may become unstable directly to an oscillatory disturbance.
Original languageEnglish
Title of host publicationProceedings of the 2004 International Conference on Computational & Experimental Engineering & Sciences (ICCES ' 04), July, 2004, Madeira, Portugal
Number of pages6
ISBN (Electronic)096570016X
Publication statusPublished - 29 Jul 2004
EventThe 4th International Conference on Computational and Experimental Engineering and Science, ICCES 04 - Madeira, Portugal
Duration: 26 Jul 200429 Jul 2004

Conference

ConferenceThe 4th International Conference on Computational and Experimental Engineering and Science, ICCES 04
CityMadeira, Portugal
Period26/07/0429/07/04

Keywords

  • Marangoni effect
  • fluid-dynamics
  • floating zones
  • flow instability
  • numerical simulations

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