Influence of Geometrical Aspect Ratio on the Oscillatory Marangoni Convection in Liquid Bridgesum

Abstract

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Stability of thermocapillary flow in liquid bridges fully coupled to the gas phase

“… A first variation, which is typically made in laboratory experiments, is a variation of the length of the liquid bridge (Velten et al. 1991; Monti, Savino & Lappa 2000; Nienhüser & Kuhlmann 2003; Melnikov et al. 2015), corresponding to a variation of .…”

Active Electrostatic Control of Liquid Bridge Dynamics and Stability

“…The slenderness of the molten bridge has been shown to affect the shape of the solid‐melt interface 1. Thermocapillary‐flow experiments in model half‐zones show that the complexity of the flow depends on the slenderness, with the complexity increasing for decreasing slenderness 2–4. Active electrostatic control of the molten zone could allow for a larger range of molten zone lengths to be used in the FZ process.…”

Influence of the System Geometry on the Characteristics of the Surface Tension Auto-oscillations: A Numerical Study

“…2 When the ratio of the characteristic horizontal and vertical dimensions (aspect ratio) is on the order of unity, the instability development is strongly dependent on the system geometry. [13][14][15][16][17][18] The selection of the flow pattern is related to the aspect ratios in experiments with confined geometry. Moreover, a decrease of the aspect ratio leads to the system stabilization, i.e., to an increase of the critical value of the Marangoni number (Ma).…”

“…A common object for the observation of Marangoni instability is a liquid layer with a gradient of temperature or concentration that is imposed perpendicular to the free surface or along it − The selection of the flow pattern is related to the aspect ratios in experiments with confined geometry. Moreover, a decrease of the aspect ratio leads to the system stabilization, i.e., to an increase of the critical value of the Marangoni number (Ma).…”