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Updated: Jun 23, 2026

Film Control to Study Contributions of Waves to Droplet Impact Dynamics on Thin Flowing Liquid Films
Published on: August 18, 2018
Instabilities and waves in thin films of living fluids
Sumithra Sankararaman1, Sriram Ramaswamy
1Centre for Condensed Matter Theory, Department of Physics, Indian Institute of Science, Bangalore 560012, India. sumithra@physics.iisc.ernet.in
Abstract:
We formulate the thin-film hydrodynamics of a suspension of polar self-driven particles and show that it is prone to several instabilities through the interplay of activity, polarity, and the existence of a free surface. Our approach extends, to self-propelling systems, the work of Ben Amar and Cummings [Phys. Fluids 13 1160 (2001)10.1063/1.1359748] on thin-film nematics. Based on our estimates the instabilities should be seen in bacterial suspensions and the lamellipodium, and are potentially relevant to the morphology of biofilms. We suggest several experimental tests of our theory.
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