Solitary waves on superconfined falling liquid films

Abstract

Solitary waves on the surface of a vertically falling liquid film in contact with an extremely confined counter-current gas flow are studied numerically. As the gas velocity is increased, traveling waves display a secondary oscillatory instability and then a catastrophic instability. The periodic amplitude modulations produced by the oscillatory instability intensify mixing and can be tuned through the gas velocity. The catastrophic instability leads to wave reversal and liquid arrest.

Topics & Concepts