Characterization of atmospheric pressure H2O/O2 gliding arc plasma for the production of OH and O radicals

Atmospheric pressure H2O/O-2 gliding arc plasma is generated by a 88 Hz, 6 kV AC power supply. The properties of the produced plasma are investigated by optical emission spectroscopy. The relative intensity, rotational, vibrational, excitation temperatures and electron density are studied as a function of applied voltage, electrode spacing, and oxygen flow rate. The rotational and vibrational temperatures are determined simulating the OH(A(2)Sigma(+)(v = 0) -> X-2 Pi(v' = 0) bands with the aid of LIFBASE simulation software. The excitation temperature is obtained from the CuI transition taking non-thermal equilibrium condition into account employing intensity ratio method. The electron density is approximated from the H-alpha Stark broadening using the Voigt profile fitting method. It is observed that the rotational and vibrational temperatures decrease with increasing electrode spacing and O-2 flow rate, but increase with the applied voltage. The excitation temperature is found to increase with increasing applied voltage and O-2 flow rate, but decrease with electrode spacing. The electron density increases with increasing applied voltage while it seems to be in a downward trend with increasing electrode spacing and O-2 flow rate. Published by AIP Publishing.