Effect of Plasma Actuation on Impact, Dynamics, and Evaporation of Water Droplet on a Room-temperature Surface

The new concept of the anti-/de-icing method based on Alternative-Current high voltage-driven surface dielectric barrier discharge (AC-SDBD) plasma actuation has no complicated mechanical structure and potential aerodynamic loss, making it potential to be the anti-and de-icing methods used by next-generation aircraft. AC-SDBD plasma actuation will produce thermal, aerodynamic, chemical and electromagnetic effects, etc. Existing studies have shown that the coupling characteristics of aerodynamic and thermal effects are the main mechanisms of plasma icing control. To provide a deep mechanism description, the plasma actuation on the impact, dynamics, and evaporation characteristics of water droplets is of great significance and researched in the present paper. High-speed imaging technology and surface infrared temperature measurement were used to record the impact and post-impact process of water droplets on the surface of the plasma actuator. The impact, dynamics, and evaporation of the water droplet with plasma actuation during this process were studied. The experimental results show that the water droplet spreads over the covered electrode in a larger range with plasma actuation, and the maximum spreading coefficient increases in comparison with those of plasma-off. The plasma actuation has an obvious driving effect on the water droplet during the impact and post-impact process. The water droplet can be driven 5 mm downstream from the joint of the exposed and covered electrodes. With unsteady-on plasma actuation, the water droplet presents an obvious oscillate performance. All the break-up water droplets will completely evaporate within 50 seconds.