Cross-sectional of capacitance measurement in-transition of particle concentration in microchannel system

Abstract

In a present study, capacitance sensing is used as a visualization method for determination of dielectric permittivity distribution in microchannel system from external capacitance measurement. The microchannel had fabricated using micro-electro-mechanical-systems (MEMS) advanced technology which has two inlets and outlets and five cross-sections that each cross-section was embedding with 12 electrodes pair that connected to the microchannel system. The capacitance sensing had measured at cross-section III and V at different condition of inlets injection which cross-section III is located at the center of microchannel while cross-section V is nears the outlets. The dynamic behaviors of 6.0µm of polystyrene particles and deionized water are investigated by using capacitance sensing and particles concentration distribution in a presence of non-uniform electric fields of micro electrodes are studied in details. The permittivity and concentration of particles in term of a particle volume fraction are calculated at different zone of the microchannel area measurement. The microchannel area measurement are divided into three different zones which zone I is a measurement near a wall, zone II is a measurement halfway between centerlines and the wall and zone III is a measurement at the centerlines of microchannel system. The particles are more concentrate in zone I and zone II which is the area between centerlines of microchannel and near the wall that indicates a migration of particles are happen in the microchannel that seems to be reflect to the Serge-Silberberg phenomenon.