Date and Time: 09/22/2023, 14:00--15:00

Location: https://gsumeetings.webex.com/gsumeetings/j.php?MTID=m7841791d79316892a83e933f2c3f456c

Colloquium: Theory for undercompressive shocks in tears of wine

Speaker: Prof. Andrea Bertozzi, UCLA

Speaker's website: https://www.math.ucla.edu/~bertozzi/

Title: Theory for undercompressive shocks in tears of wine

Abstract: Prof. Bertozzi will give a talk on this problem:

https://www.winespectator.com/articles/dry-your-eyes-wine-tears-finally-explained-by-science-unfiltered

Abstract: We revisit the tears of wine problem for thin films in water-ethanol mixtures and present a model for the climbing dynamics. The formulation includes a Marangoni stress balanced by both the normal and tangential
components of gravity as well as surface tension which lead to distinctly
different behavior. The prior literature did not address the wine tears
but rather the behavior of the film at earlier stages and the behavior of
the meniscus. In the lubrication limit we obtain an equation that is
already well known for rising films in the presence of thermal gradients.
Such models can exhibit nonclassical shocks that are undercompressive. We
present basic theory that allows one to identify the signature of an
undercompressive wave. We observe both compressive and undercompressive
waves in new experiments, and we argue that, in the case of a preswirled
glass, the famous “wine tears” emerge from a reverse undercompressive
shock originating at the meniscus.

This is joint work with Yoni Dukler, Hangjie Ji, and Claudia Falcon.

Host: Pejman Sanaei (psanaei@gsu.edu)