We study the ac-field-driven segregation of positively polarized particles flowing through a micro-channel. Our batch fabrication technique allows one to construct an apparatus featuring a large number of mechanically robust and chemically inert micro-devices having a very low ratio of the dielectrophoretic time to the fluid residence time. Experiments were performed on dilute suspensions in microfluidics with electrodes of different sizes arranged parallel and perpendicular to the flow. The application of a high-gradient strong ac field to a flowing suspension results in trapping particles in the channel. When the channel characteristics meet certain requirements, the predictions of a single-particle model for the particle accumulation along the channel are found to be consistent with the experimental data. The model calculations required no fitting parameters because the suspension properties were measured independently. The results of our studies validate a simulation model needed for the design and operation of dielectrophoretic micro-fluidics.
|Original language||English (US)|
|Number of pages||5|
|Journal||American Society of Mechanical Engineers, Materials Division (Publication) MD|
|State||Published - Jan 1 2003|
|Event||2003 ASME International Mechanical Engineering Congress - Washington, DC., United States|
Duration: Nov 15 2003 → Nov 21 2003
All Science Journal Classification (ASJC) codes