Investigation of electrical and spectral characteristics of water falling film DBD in different gases

Abstract

Along with widespread use in industrial processing, non-thermal plasma sources proved to be effective for the treatment of polluted water. In order to achieve the best results in water treatment, we designed and constructed the coaxial plasma reactor with water falling film. Efficiency of this reactor is based on the existence of many reactive species and UV radiation in plasma that is formed above the water. An experimental study of coaxial dielectric barrier discharge (DBD) operating in gas and in gas with water is presented. We have investigated electrical and spectroscopic characteristics of DBD in nitrogen, air, helium and argon at atmospheric pressure. The influence of applied frequency on discharge power and emission spectrum is studied in order to achieve the optimum working conditions of DBD reactor. Experimental results demonstrate that in the applied frequency range of 50 to 450 Hz the best operating conditions are reached at a frequency of 300Hz. Emission spectrum of DBD in nitrogen and nitrogen with water show that NO γ bands are not present in the discharge with water.