Influences of water vapor volume fraction on discharge characteristics of dielectric barrier discharge in Ar

The influences of water vapor addition on discharge characteristics of dielectric barrier discharge (DBD) were studied by electrical and optical diagnostics. The voltage-current waveforms, light-emission pictures, and emission spectroscopy were measured, and then the discharge parameters such as discharge power, transported charge, electron excitation temperature as well as vibrational temperature and rotational temperature were calculated to study their changing tendencies in the presence of water vapor content. Moreover, the influences of water vapor addition on discharge characteristics of DBD were analyzed by combining discharge mechanism. Results show that when the amplitude of applied voltage is fixed, with the increase of the water vapor content, the lighting emission intensity becomes weak and the discharge filaments become more and more dense, the uniformity of discharge improves, the discharge power and transported charge decreases, but the rotational temperature and vibrational temperature increases. The gas temperature for DBD in argon/water mixtures varies between 610 K and 2600 K. The intensity of the main active particles reaches their maximum values at water vapor content of 0.1%, and it has higher activity.