Abo Bibliothek: Guest

ISSN Online: 2377-424X

ISBN Print: 978-1-56700-474-8

ISBN Online: 978-1-56700-473-1

International Heat Transfer Conference 16
August, 10-15, 2018, Beijing, China

UNVEILING THERMOCAPILLARY CONVECTION IN PURE WATER DROPS

Get access (open in a dialog) DOI: 10.1615/IHTC16.bae.023953
pages 809-814

Abstrakt

The existence of thermocapillary/Marangoni convection in pure water drops has been a hotly debated area over the last few years. In this paper, we report the induction of Marangoni convection in pure water drops by localized laser heating and visualized via high speed infrared and optical cameras. The optical camera recorded the evolution of drop shape over time and the infrared camera provided the spatiotemporal evolution of the temperature across the surface of the water drop. Localized heating induced a temperature gradient, which gave rise to a surface tension and eventually thermal and liquid flows within the drop. This flow manifested as twin vortices, which after experimental and theoretical arguments was attributed to Marangoni convection. We present, here, the influence of surface wettability which was found to play a major role in the convective patterns. Moreover, heating location and power on both the Marangoni convection patterns and the evaporation kinetics of the drops.