Influence of waterdrop sizes on the growth of discharge

Streamer is not only the prelude of leader discharge development, but also the important stage of lightning. In order to understand the influence of water droplet sizes on the initiation and growth of discharge, three kinds of mist with different size droplets are applied to study this influence. Based on the measurement of droplet sizes in three mist and directly comparative analyses of the percentages of the discharge path on mist or air in a non-uniform field, at atmospheric pressure, it can be concluded that mist with droplets smaller than 10 µm suppresses the lightning discharge, and has the negative impact on the first step of discharge; mist with droplets greater than 10 µm has the inhibited effect on the starting and growth of positive discharge, but has the contrary effects on negative discharge. These droplets in mist distort the electrostatic field, interact with ions, electrons or photons, and produce corresponding enhancements or decreases in ionization and excitation as the avalanche front encounters them, but the details of different degree alterations on avalanches highly correlate with the droplet sizes.