Interaction between negative corona discharge and vapour condensation in steam jets

Ion-induced condensation has attracted increasing attention in the field of atmospheric precipitation. Supersaturation plays an important role in promoting vapour condensation. This study explores the interaction between supersaturated vapour and corona discharge by examining the characteristics of negative corona discharge in a steam jet and its effect on the condensation of supersaturated steam. Experiments were conducted using two steam jets with different degrees of supersaturation. The voltage-current curve of the corona discharge and the distribution characteristics of the droplet size and concentration along the central axis of the steam jet were evaluated. The results showed that the steam jet suppressed the corona discharge, while the corona discharge enhanced condensation within the jet. The concentration of condensed droplets in steam jets with higher supersaturation was more strongly influenced by corona discharge than in jets with lower supersaturation. Calculations indicated that the attachment coefficient in supersaturated water vapour was higher than in air, contributing to the suppression of the corona discharge within the steam jet. Ions introduced by the corona discharge reduced the Gibbs free energy required for droplet condensation in the steam jet, with a greater reduction in highly supersaturated steam jets. These findings provide insights into the mechanisms through which corona discharge influences steam jet condensation, suggesting potential applications in optimizing charged steam jets.