The Dynamic contact angle

Spreading of Liquids on Dry and Pre-Wet Solid Surfaces

“…4, it is shown that even a very thin microscopic film (p s es = 0.1) strongly decreases 0d even for positive p s es . In complete agreement with 0.001 experimental observations, the dynamic advancing contact angle associated with the flow over a pre-wet solid surface is lower than that obtained for the dry solid surface 14 ' 15 , and, if the static contact angle in both cases is the same 14 , 0d increases not so rapidly in the case of a pre-wet solid surface as it does if the surface is dry. Quantitative comparison with the above-cited experiments is difficult due to the lack of information about some parameters involved in the theory.…”

Spontaneous spreading of surfactant-bearing drops in the sorption-controlled limit

“…3 for a soluble surfactant with Bi = 1. These values of m approximately represent the two ends of the range of experimentally observed values for spreading of pure liquids [6,7]. For fixed equilibrium contact angle, the predicted spreading dynamics are relatively insensitive to the value of m, with a surfactant-retarded spreading regime followed by surfactantenhanced spreading in both cases.…”

“…(2) which is a constitutive equation relating the contact line velocity to the dynamic contact angle. The power-law dependence of the contact line velocity on contact angle has been verified experimentally for the spreading of pure liquids [6,7], with the power-law index m taking on values in the range of 1 to 3. In Eqs.…”

Wetting boundary condition for the color-gradient lattice Boltzmann method: Validation with analytical and experimental data

“…However, the contact angle during capillary rise does change. There have been several experiments that have measured the dynamic contact angles as a function of capillary number (for instance, Hamraoui and Nylander, 2002;Hoffman, 1975;Rillaerts and Joos, 1980 ). In this section, we refer to Heshmati and Piri (2014) 's experiment.…”