AC electrothermal effect generates temperature gradients in the fluids, consequently inducing free charges that move in electric fields, and produce microflows in microchannel. This paper reports dramatic improvements in flow rate over conventional ac electrokinetic micropumps by exploiting asymmetry in electric potentials over the electrodes. A micropump consisting of planar asymmetric electrode array was tested using AC signals with and without a DC bias. The pumping velocity is much faster with a DC voltage, in some cases by an order of magnitude, reaching 3.2 mm/sec linear velocities with only 9 Vrms. Our hypothesis attributes the increase of ACET force to the ion generation near electrode by reactions and the resulting high conductivity gradient. The discovery presents an exciting opportunity for microfluidics, and further improvement can be anticipated with some optimization.
- Nanotechnology Institute
Ultra Fast Micropumping by Reaction Enhanced AC Electrothermal Effect
- Views Icon Views
- Share Icon Share
- Search Site
Lian, M, Wu, J, & Mruetusatorn, P. "Ultra Fast Micropumping by Reaction Enhanced AC Electrothermal Effect." Proceedings of the ASME 2009 Second International Conference on Micro/Nanoscale Heat and Mass Transfer. ASME 2009 Second International Conference on Micro/Nanoscale Heat and Mass Transfer, Volume 1. Shanghai, China. December 18–21, 2009. pp. 217-221. ASME. https://doi.org/10.1115/MNHMT2009-18387
Download citation file: