Enhanced water capture induced with electrowetting-on-dielectric (EWOD) approach

An electrowetting-on-dielectric (EWOD) device that enhances water capturing capability for condensation applications is presented. A single planar EWOD device is fabricated for testing and placed in a high-humidity environment under mist flow. By applying an electric field to portions of the device, the wettability of the affected areas is altered from hydrophobic to hydrophilic, which promotes droplet nucleation and growth, thereby improving water capturing capability. The results of this study demonstrate that droplet coalescence is appreciably improved at the moments of plugging and unplugging DC voltage, which induces wipe-down events (when a droplet drips down the surface and removes all droplets underneath it). The improvement in water capturing capability under DC voltages of 20 V, 40 V, and 60 V is also investigated both by comparing the mass of water collected on uncharged and charged devices during the same testing period and by using an image processing approach to track changes in droplet area...