Photoelectric characteristics of volume diffuse DBD in air and water mist

Abstract

Photoelectric characteristics are very important for discharge plasma. A volume diffuse dielectric barrier discharge (DBD) by means of parallel-plate arrays was established, and the methods including electrical parameter and optical emission spectroscopy (OES) were used to diagnose the discharge parameters. The results show that the spectra from discharge both in air and water mist have same trends, and the spectra of hydroxyl radical in water mist are stronger than those in air. However, the energy efficiency ratio (EER) of quantum yield of 337.1nm from N2 presents a functional relationship under different discharge voltage and power. The EER increased with increasing discharge voltage from 32.5kV to 34.5kV, and decreased with decreasing discharge voltage less than 28.5kV in air. It has not contribution for EER with discharge voltage under 30.5kV in water mist. Meanwhile, both the multiple breakdowns and intensity in the discharge current waveform from DBD in air are more prominent than those in water mist. When the input power of high voltage power source is a constant, the discharge power of DBD cell within both air and water mist increased with increasing discharge voltage. Moreover, the equivalent capacitances of the DBD cell, quartz insulating layers and discharge gaps have some relationships with discharge power and voltage. When the discharge voltage is a constant (32.0kV), the equivalent capacitances of both DBD cell and gaps with discharge in air maintained same trends and looked like sine curves with increasing discharge power. The equivalent capacitance of insulating layers slightly increased firstly and then slightly declined with increasing discharge power. Furthermore, the equivalent capacitances of DBD cell, insulating layers and gaps with discharge in water mist maintained as probably different constants, respectively. This work demonstrated the close coupling of the photoelectric characteristics of the discharge voltage and power of volume diffuse DBD, and thus is helpful in the study of the application of volume DBD.