A system was developed to study electrostatic force control in mesoscale and microscale fluidic phenomena. Utilizing the polarization (dielectrophoretic) force in a simple planar electrode configuration, control of a liquid-bubble interface is achieved. By applying a +dc voltage a 1Hz switching frequency to an array of four electrode pairs, pumping was produced with four fluids covering a wide range of electrical properties; the range of dielectric constant and electric conductivity was over 1 order of magnitude and 5 orders of magnitude, respectively. Simple analysis and initial experimentation provide evidence that the normal polarization stress at the liquid-bubble interface and surface tension are the primary driving force and retarding force, respectively that affect bubble motion.

Volume Subject Area:
Fluids Engineering
Topics:
Bubbles, Electrodes, Polarization (Electricity), Polarization (Light), Polarization (Waves), Electrical conductivity, Electrical properties, Fluids, Force control, Microscale devices, Stress, Surface tension
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