T0501-1-3 白金上の水の動的接触角に対する温度の影響に関する分子動力学解析([T0501-1]マイクロ・ナノスケールの熱流体現象(1))

Abstract

Microscopic contact angle at a moving contact line among water-vapor-platinum interfaces was investigated with molecular dynamics calculations. The extended simple point charge (SPC/E) model was used for the water molecules and the interactions between water and platinum plate were calculated with the potential model proposed by Zuh and Philpott(1994). The simulations were performed in a Couette flow geometry in which water slug were placed between two parallel plates of platinum. The simulation results show that the static contact angle decreased with the increment in the temperature. The dynamic contact angle, which depends on the wall velocity Vw, became less sensitive to Vw as the temperature was increased. The ordered structure of the water molecules was observed in the vicinity of the wall surface, and was disordered as the temperature was raised. This should be responsible for the lowering of the sensitivity of the dynamic contact angle in the high temperature condition.