A Numerical Investigation on the Reactive Species Generation and Its Correlation With Electron Energy in Atmospheric-Pressure Helium/Humid Air Plasma Jets

In this work, the reactive species generation and its correlation with electron energy in atmospheric-pressure helium/humid air plasma jets have been numerically investigated based on a needle-plane electrode geometry by using a 2-D fluid model. With the increase in the voltage amplitude, the averaged electron energy increases, the respective averaged densities of OH, O(
¹
D), and O
^-
increase, while the averaged H
₂
O
₂
density decreases. Therefore, between the species generation and electron energy, there is a negative correlation for H
₂
O
₂
and a positive correlation for OH, O(
¹
D), and O
^-
. In addition, as the humid air concentration increases, the averaged electron energy decreases, but the respective averaged densities of OH, O(
¹
D), O
^-
, and H
₂
O
₂
increase. Consequently, there is a negative correlation between these species generations and electron energy. Finally, this work shows that a proper high humid air concentration in the plasma jets applied for biomedicine may allow expected electron energy and also generate abundant reactive species.