A TRAVELING-WAVE MICROPUMP FOR AQUEOUS-SOLUTIONS - COMPARISON OF 1-G AND MU-G RESULTS

The operation of a micro-chip-based fluid circulator based on the inte raction of a high-frequency traveling wave with a thermally generated inhomogeneity in an aqueous medium is investigated. The profiles of th e electric field, the thermal gradient and the driving force within th e device are derived numerically, and the dependence upon applied volt age under different experimental conditions is derived. The importance of convection in the operation of the device is assessed by operating it in various orientations, as well as under microgravity, and also b y investigating the reversal and turn-on characteristics. The pump sho wed the unexpected ability to trap microparticles present in the drive n fluid.