ICONE15-10242 Molecular Dynamics Study on the Dependence of Contact Angle on the Speed of Contact Line

Abstract

Wetting phenomena greatly affects boiling or condensing phenomena of liquid on the solid surface. Although the contact angle is one of the most important parameters to represent the wetting condition, the behavior of the contact angle is not understood well, especially in the dynamic condition. In this study, molecular dynamics (MD) simulations were made to investigate the dependence of microscopic contact angle on the speed of contact line, ΔV, under a condition where fluids near the wall crystallized. The results were then compared with an estimation obtained by substituting velocity distribution by Huh's theory (1971) into Qian's statement of stress balance near the contact line (2003). The estimation well reproduced the MD results on the dependence of the contact angle on ΔV. The value of ΔV in MD results is limited below a certain value; above it, contact line follows the wall motion and ΔV is suppressed below the limit. This phenomenon is also reproduced by this estimation method.