A novel electrokinetic micromixing system with conductive mixing-enclosure-A geometrical study

In this paper, an electrokinetic micromixing system with conductive mixing-enclosure is proposed. The simulated micromixer can be fabricated easily and accordingly, it can be used in the microfluidic systems effectively. The mixing process is intensified by controlling the geometry of the mixing-enclosure and electric field strength. The effects of different parameters including existence of mixing-enclosure, horizontal and vertical sizes of mixing-enclosure, orientation angle of mixing-enclosure, and electric field strength on the mixing index are studied. The mixing efficiencies and mixing lengths of current electrokinetic micromixer and those previously proposed by other researchers are compared. The results showed that the mixing efficiency can be enhanced significantly as a micromixer with conductive mixing-enclosure is employed. As an advantage of the proposed micromixer, the maximum mixing efficiency does not change by boosting the electric field strength in the range of 100 V.cm-1 to 200 V.cm-1, while the mixing time diminishes as the electric field strength increases in this range. For the conductive mixing-enclosure with the orientation angle of 45°, maximum mixing efficiency of 96.6% is achieved by exerting electric field with strength of 75 V.cm-1. The current electrokinetic micromixer has superior mixing efficiency and mixing length as compared with other electrokinetic micromixers.