Evolution of a single sessile droplet under the influence of the dielectric barrier discharge plasma actuator

Abstract

Ice accretion on airplane surfaces has been widely recognized as a significant safety threat, and corresponding investigations of anti-/de-icing technologies have experienced tremendous growth during the last two decades. Dielectric barrier discharge plasma actuators involve different characteristics, such as thermal, acoustic, and flow characteristics, which are well suited for reducing and preventing ice accretion on wing surfaces effectively and safely. However, the correlation between the droplet, as the core of ice formation, and the plasma actuator is still not very clear. In order to understand the anti-/de-icing mechanism of the plasma actuator further, the evolution of a single sessile droplet under the influence of a symmetrical plasma actuator is studied. Interestingly, the oscillation of the droplet is first observed on the initiation of the plasma actuator, which is quite different from the droplet variation under traditional heating or cooling. Then, the flow field inside the droplet under the effect of the induced flow field of the plasma actuator is first uncovered by using the particle image velocimetry system. Subsequently, the evolution process of droplet deformation, deformed droplet moving downstream, deformed droplet moving downstream and evaporating, and water film moving downstream and evaporating is revealed. In addition, the underlying mechanism of the evolution process of the droplet is discussed based on the different characteristics of the plasma actuator. This study provides an in-depth understanding of the correlation between the droplet and the plasma actuation and lay a foundation for proposing the optimized strategy of anti-/de-icing using plasma actuators.