Flexible Electrohydrodynamic Fluid-Driven Valveless Water Pump via Immiscible Interface

Abstract

The conventional electrohydrodynamic (EHD) pump is limited to pumping functional and dielectric liquids, which restricts its applications in fields like microfluidics, food safety, and materials production. In this study, we present a flexible water pump driven by EHD fluid, achieved by integrating valveless elements into the fluidic channel. Our approach leverages the water–EHD interface to propel the immiscible aqueous liquid and reciprocate this process using the nozzle–diffuser system. All components of the water pump are digitally fabricated and assembled. The valveless parts are created using a laser cutting machine. Additionally, we develop a model for the EHD pump and nozzle–diffuser system to predict the generated flow rate, considering factors such as the asymmetrical performance of the EHD pump, pulse frequency, applied voltage, and structural parameters. Finally, we experimentally characterize the flow rates of both the EHD pump and water pump and apply the newly developed device to air bubble manipulation and droplet generation. This research broadens the range of specialized liquids pumped by EHD pumps to include other aqueous liquids or mixtures.