演講快訊

2021
10.29

Capillarity Revisited 再談毛細現象

曹恆光 教授

時間:2021年10月29日 (五) 15:10 PM
主持人:鄧熙聖 主任
講者:曹恆光 教授
服務單位:中央大學 化學工程與材料工程系
講題:Capillarity Revisited 再談毛細現象
地點:華立廳 & Webex線上同步

摘要 :

Capillarity or capillary effect is the phenomenon that liquid spontaneously flows in a narrow space without the assistance of external forces. It is frequently observed in nature and life, and occurs due to intermolecular forces between the liquid and surrounding solid surfaces (liquid-solid tension), and those between the liquid and air (liquid-gas tension). The competition between cohesion within the liquid and adhesion between the liquid and wall acts to propel the liquid. Although capillarity has been extensively studied since the early 19th century, it is very much alive fundamentally in nanoscale phenomena and technologies. In this talk, first, the criterion for capillary imbibition to take place is examined based on free energy minimization (thermodynamics). The edge effect which resists wetting is introduced as well. Then, capillary flow in open channels is investigated and compared to well-known Washburn’s equation (transport phenomena). Finally, the question whether capillary flow can pass over a hole or not is explored from simulations.

學經歷 :

BS & MS  NTU  

PhD  Cornell