Coagulation cascade of surface plumes in viscoelastic rimming flow

We report the experimental observation of Kolmogorov-type steady coagulation cascade in an elastically driven instability occurring at the liquid front of a dilute polymer solution partially filling a rotating horizontal drum. Surface plumes are found to dominate the flow in the vicinity of the front at low Reynolds numbers. Plume merging leads to an area cascade with a time-independent mass flux. The coalescence process results in a power-law decay of the stationary plume area distribution, with an exponent which agrees with that of the Smoluchowski coagulation model.