Measuring contact line dissipation in dynamic wetting
200? (English)Report (Other academic)
Dynamic wetting of a solid surface is a process that is ubiquitous in nature, and also of increasing technological importance. The underlying dissipative mechanisms are however still unclear. We present here dynamic wetting experiments of a droplet on a dry surface, showing that an important part of the dissipation may arise from a friction related to the motion of the contact line itself, and that this may be dominating the viscous friction in the flow adjacent to the contact line. By a combination of simulations and experiments, values of a corresponding friction factor are obtained. By this procedure the contact line friction factor can be distinguished and quantified, also in room temperature where other sources of dissipation are present. Water and glycerin-water mixtures on various surfaces have been investigated. We show the dependency of the friction factor on the nature of the surface, and the viscosity of the liquid.
Place, publisher, year, edition, pages
200?. , 14 p.
Fluid Mechanics and Acoustics
IdentifiersURN: urn:nbn:se:kth:diva-34574OAI: oai:DiVA.org:kth-34574DiVA: diva2:422041
QC 201106102011-06-102011-06-102011-06-10Bibliographically approved