Abstract
In a present study, a micro particle concentration in the microchannel with 12 embedded sensor electrodes is measured based on the temporally transitional cross-sectional capacitance measurement. The accurate capacitance measurement system is designed based on the stray immune electrical circuit. The temporal transition of the cross-sectional capacitance of deionized water and polystyrene particle at the adjacent electrode pair is measured at the cross-section near the microchannel outlets. The experiment result shows the cross-sectional capacitance is decreased gradually when the presence of lower dielectric material in the microchannel flow. The particles concentration is calculated in the terms of particle volume fraction based on the cross-sectional capacitance measurement. The particle volume fraction is slightly proportional with the time measurement because the particles slowly migrated and transported in the microchannel flow. The particle volume fraction at near the microchannel wall is 13.3% increased after the temporal transition at 8,000 ms and fully to concentrate at 13,000 ms at the cross-section V; near the outlets.
