Advances in nanotechnology allows for electrodeposition and fabrication of micro/nano electrodes between substrates of microfluidic channels which later can be used as electrodes to apply DC or AC voltage. Microchannels taking advantage of this technology have shown promising results in flow cytometry [1,2], and cell sorting applications [3–6].
In this paper, first we study the influence of electric potential on particle sorting in a microchannel. For this purpose, a two dimensional computational fluid dynamics (CFD) model is created, meshed and solved in STAR-CCM+ which is a commercial simulation tool. Two type of spherical solid particles with different diameter are introduced through an injector from particulate flow inlet. These solid particles are treated as Lagrangian phase. The simulations are conducted in transient mode and the particle injection is occurred once the flow regime became steady state. The proposed model is based on finite volume approach and confirms the effectiveness of dielectrophoresis on particle sorting.
In the second part of this work, we focus on optimizing the separation efficiency of microchannel by implementing Siemens exclusive automated design exploration technology named SHERPA. Through this hybrid and adaptive strategy we investigate 4 key parameters including electric potential, flow velocity at two inlets, and particle mass flow rate. The objective is to minimize the electric potential while maximize the efficiency of device, measured by amount of particles separated at the outlet. In total 40 designs are evaluated. The results show that by adjusting the flow rate ratio between inlets, and applying a low voltage such as 5 V, you can increase the mass flow rate of segregated particles by approximately 100 times.
The proposed model not only can help shortening the time to market for new dielectrophoresis based channels, but also be used to optimize the overall device performance to achieve the best separation efficiency at optimal condition.