Title: Wetting on a Plate with Three-Dimensional Random Heterogeneity and Roughness. Contact Angle Hysteresis.
Abstract:The hysteresis phenomena of solid-liquid contact angles were investigated theoretically by using the result of the preceding report that the hysteresis is caused by the irreversibility of energy chang...The hysteresis phenomena of solid-liquid contact angles were investigated theoretically by using the result of the preceding report that the hysteresis is caused by the irreversibility of energy change of wetting behavior between liquid advancing and receding on the solid surface. The energy was calculated for the system composed of a meniscus attached to a vertical solid plate with three-dimensional random roughness and heterogeneity. The irreversible movement occurs in the different manner between advancing and receding, which causes the difference of the system energy change. The contact angles calculated from the thermodynamically stable condition showed that the advancing (receding) contact angles were maximum (minimum) ones among those which locally satisfies Young's equation. The contact angle hysteresis can be expressed by the sum of the energy dissipation occurring at the advancing and receding.Read More