Plasma-Produced Reactive Species Interactions with Liquid Water Droplets

The transport of plasma produced reactive species to liquid droplets in atmospheric pressure plasmas produces chemically active liquids for biotechnology and agriculture. Droplets having large permittivity are electrically dynamic due to their polarization which in turn affects production of ions and radicals in their vicinity. Charging and evaporation of the droplet additionally complicate the interaction with the plasma. In this talk, we discuss activation of a liquid water droplet by an atmospheric pressure He radio frequency glow discharge. To better understand the interactions of short-lived reactive species and the droplet, formate (HCOO^-_aq) is dissolved in the droplet, and the change in HCOO^-_aq concentration quantifies the interactions between OH_aq and the droplet. These interactions are computationally investigated using the 0D model GlobalKin and the 2D model nonPDPSIM. On a time-averaged basis, the polarization of the droplet maximizes the electron temperature near the poles of the droplet, producing more reactive species at that location. The results of the models will be compared to companion experiments.