Thursday, 24 January, 2008
Microfluidic Mixing via Acoustically Driven Chaotic Advection
T. Frommelt, M. Kostur, M. Wenzel-Schäfer, P. Talkner, P. Hänggi, and A. Wixforth -
Phys. Rev. Lett. 100, 034502 (2008)
Mixing presents a notoriously difficult problem in small amounts of fluids. Herein, surface acoustic waves provide a convenient technique to generate time-dependent flow patterns. These flow patterns can be optimized in such a way that advected particles are mixed most efficiently in the fluid within a short time compared to the time pure diffusion would take. Investigations are presented for the mixing efficiency of a flat cylinder that is driven by two surface acoustic waves. The experimental results favorably agree with model calculations of the flow patterns and the advective transport.