This paper was an attempt to investigate, through numerical simulation, the designs of DEP flow sorters when applied with different ratios of the electrodes to generate different electrical fields, and to explore the sorting capability of the flow sorters, defined as the degree of particle deflection, under different operation of parameters.
In order to obtain the maximal DEP negative particle deflection, which was believed as an indicator of greater sorting capability, we have investigated different non-uniform electrical fields produced by combinations of electrodes with different length of two poles, ranging from 1:2 up to 1:9. The finding of numerical simulation indicated that the length ratio 1:3 of the electrode poles produced the electrical fields that maximized the particle deflection.
Moreover, different parameters of applied voltage, flow rate, particle diameters, and distance between two electrical poles were designed to investigate their effects on particle deflection of flow sorters. The numerical simulation of the study showed that the DEP flow sorter was demonstrated as a linear system with respect to the applied voltage and particle diameter. In this study, we tried to operationally define flow rate as the time duration while the flow passed the electrical fields, and thus investigated how particle deflect with the different time given. We found that the particle deflected more when the flow was allowed with longer time to pass the electrical fields. The study also showed that the distance the particles deflect from the centerline is in inverse proportion to the square distance between the two electrical poles.