Daphne Klotsa , University of North Carolina We describe experiments and simulations demonstrating the propulsion of a neutrally buoyant swimmer that consists of a pair of spheres attached by a spring, immersed in a vibrating fluid at intermediate Reynolds numbers. The vibration of the fluid induces relative motion of the spheres which, for sufficiently large amplitudes, can lead to motion of the center of mass of the two spheres. We find that the swimming speed obtained from both experiment and simulation agree and collapse onto a single curve if plotted as a function of the streaming Reynolds number, suggesting that the propulsion is related to streaming flows. There appears to be a critical onset value of the streaming Reynolds number for swimming to occur. We observe a change in the streaming flows as the Reynolds number increases, from that generated by two independent oscillating spheres to a collective flow pattern around the swimmer as a whole. The mechanism for swimming is traced to a strengthening of a jet of fluid in the wake of the swimmer. We discuss the collective behavior and fluid flows of such swimmers.

BioActive Fluids seminar by Daphne Klotsa, UNC Chapel Hill, 22nd July 2020

New research into so-called two-sphere swimmers. Featuring Roger Bowley, Richard Hill and Kyle Baldwin. Research also by Michael Swift and Daphne Klosta. The paper at http://dx.doi.org/10.1103/PhysRevLett.115.248102 (full paper will require subscription) More videos with Professor Roger Bowley: http://bit.ly/RogerBowley Objectivity: http://bit.ly/Objectivity Visit our website at http://www.sixtysymbols.com/ We're on Facebook at http://www.facebook.com/sixtysymbols And Twitter at http://twitter.com/sixtysymbols This project features scientists from The University of Nottingham http://bit.ly/NottsPhysics Sixty Symbols videos by Brady Haran http://www.bradyharanblog.com Email list: http://eepurl.com/YdjL9

This video shows Daphne Klotsa's presentation at the "EURAXESS Share: Broaden your Horizons!", which took place in New York City on March 27th, 2014 at Columbia University. The aim of the event was to foster interactions between recipients of EU funding programs based in North America and researchers interested in applying for one of these funding schemes, as well as to showcase research projects that were successfully funded by the EU (Marie-Curie and ERC) and promote EU funding schemes. http://ec.europa.eu/euraxess/index.cfm/links/events/north_america/share Dr. Daphne Klotsa received is PhD in granular dynamics at the University of Nottingham, where she studied fluid and grain mixtures under external vibration doing both theory and experiments .During her first postdoc at the University of Bath, she studied computational models for colloids and proteins in order to understand how they assemble into ordered structures. Then, she moved to the University of Michigan as Marie-Curie Fellow, where she is currently studying the packing and self-assembly of polyhedra and other shape. More about Daphne: http://www-personal.umich.edu/~dklotsa/Daphne_Klotsas_Homepage/Home.html

Daphne Klotsa's talk at the Complex System Academic Advanced Workshop at the University of Michigan on "Patterns in oscillatory fluid flows" More information about Dr. Klotsa at http://www-personal.umich.edu/~dklotsa/Daphne_Klotsas_Homepage/Home.html