Thermoelectric Effect on Electroosmotic Flow in Microchannel

The present work reports the thermoelectric effect on electroosmotic flow (EOF) in microchannel. The thermoelectric (TE) effect on EOF was analyzed and the switch process of fluids controlled by TE unit was numerically simulated. The mathematical model was established that is composed with electrokinetics fluid, liquid-solid phase transition, and heat transfer. The microfluidic chip with the integrated TE unit was fabricated that includes the microchannel layer, heat conducting layer and refrigerating layer. As the transition from the liquid phases to the solid phase can significantly decrease electrical conductivity of electrolyte, the electrical current is available to make sure the status of phase transition. From the results, the controlling integrated TE unit is effective to close/open the EOF in microchannel. The freezing phenomena were described by results from numerical simulation and experiment.