(147c) My Research Resonance with Professor Paul H. Steen: Dancing Droplets in Outerspace

Professor Paul Steen was a giant in fluid mechanics and in understanding and describing capillary forces and related phenomena. I was lucky to have him as a colleague, mentor, and collaborator since joining Cornell as an assistant professor in 2007. In today’s talk, I will tell a story about my time working with Paul and highlight the areas where we collaborated for many years: on understanding contact line mobility and admiring the beautiful resonance shapes of sessile droplets oscillating on surfaces of various energies. This research, for me, began as a PhD student, and ends here with a trip to the International Space Station, where limitations of gravity are gone and capillary lengths grow, enabling the study of droplet dynamics at much larger scales. In our final project together, Paul and our team, sent a set of experiments to the ISS. In December, we were treated to the sight of “dancing drops” of centimeter scale, beamed down from the ISS. From these movies we could extract mobility parameters – a material parameter championed by Paul – which describe out-of-equilibrium dynamical responses of moving contact lines.