Collision and Attachment Interactions of Single Air Bubbles with Flat Surfaces in Aqueous Solutions - Drops and Bubbles in Contact with Solid Surfaces - page 234

Figure 13. Experimental data (points) and predictions (line) by hydrodynamic and molecular-kinetic
theories for TPC radius versus time [57].
is caused by the significant difference between the Young and macroscopic contact
angles. The least-squares regression analysis was used to obtain the best fit val-
ues for the model parameters, but the fitted parameters were inconsistent with the
physics involved in the models. Since neither of these models is able to describe the
experimental data, a combined model of the hydrodynamics and molecular-kinetics
is able to consistently describe the data [57] and is discussed below.
3. Crossovers of Scales
It is noted that both types of dissipation (the viscous loss in the thin liquid wedge
and the wetting line friction) do exist simultaneously [15]. Brochard-Wyart and
de Gennes [5] pointed out that non-hydrodynamic dissipation dominates at rela-
tively large value of contact angle, while the hydrodynamic dissipation prevails at
smaller contact angles. To overcome the inconsistency between these two cases sev-
eral attempts have been made for a combined theory which considers both types of
dissipation at the same time.