The instability of surface tension driven flow in models for floating zones under normal and reduced gravity

Singular ring‐shaped distribution of Nd in NdxY1‐xVO4 crystals grown by floating zone method

“…Similar aspects of the concave projection and stagnant region at the interface were reported in the FZ growth of the yttrium iron garnet, Ca:Mg 2 SiO 4 and Neodymium silicate crystals [14][15][16]. For the FZ growth, a forced convection enhanced by rotation the feed and seed is predominant in the central region of the molten zone, whereas Marangoni convection by surface-tension gradients is predominant in the peripheral region of the molten zone [17][18][19][20][21][22]. Marangoni convection and the forced convection are expected to meet at the intermediate part in the molten zone and a stagnant region will be formed.…”

Thermal convection in liquid bridges with curved free surfaces: Benchmark of numerical solutions

“…Refs. [3,4]. Recent studies investigate the role of secondary effects on the development of non-steady flow patterns in liquid bridges: free-surface deformation, heat exchange with gas environment, and extremely short or long bridges, etc.…”

Suppression of thermocapillary oscillations in sodium nitrate floating half-zones by high-frequency end-wall vibrations

“…However, in this context, thermocapillary convection, arising from the variation in the surface tension with temperature at the melt/vapor interface, becomes dominant and can lead to radial nonuniformities in dopant distribution. Further, depending on the zone properties, dimensions and the driving axial temperature gradients, the thermocapillary flow field can become nonsteady [3][4][5] with the radial inhomogeneities in dopant distribution being transformed into crystal striations [6,7]. In float zones of semiconductors and metals (low Prandtl number zones) the transition to oscillatory thermocapillary flow occurs readily at low Marangoni numbers [4,8].…”

“…Further, depending on the zone properties, dimensions and the driving axial temperature gradients, the thermocapillary flow field can become nonsteady [3][4][5] with the radial inhomogeneities in dopant distribution being transformed into crystal striations [6,7]. In float zones of semiconductors and metals (low Prandtl number zones) the transition to oscillatory thermocapillary flow occurs readily at low Marangoni numbers [4,8]. The current experiments examine the possibility of suppression of thermocapillary oscillations, in sodium nitrate half zones, through high-frequency end-wall vibrations.…”