Research on Discharge Characteristics of Flexible Dielectric DBD in Porous Media Structures

Dielectric barrier discharge (DBD) can generate low-temperature plasma with a simple structure and has been widely studied in the field of plasma. In this article, a porous flexible DBD (PF-DBD) device composed of polyimide and soda-lime glass (SLG) is designed. Driven by a pulse power supply, the discharge characteristics of PF-DBD are similar to traditional DBD discharge; two discharges occur within one pulse cycle. As the voltage increases, the discharge gradually spreads from the edges of the hole toward the center, eventually covering the entire hole. An equivalent circuit model of PF-DBD is established, and plasma discharge power, charge transfer, and discharge efficiency are calculated. As the aperture increases, the plasma distribution at the center of the hole gradually becomes uniform, and the discharge morphology changes from filamentous discharge to glow discharge. Correspondingly, the transfer of charge and discharge efficiency also increased. As the number of holes increases, the electric fields between adjacent holes interact through mutual shielding and cancellation effects, resulting in a more uniform overall electric field distribution. The uniformity of discharge, discharge efficiency, and transfer of charge also increase accordingly. Finally, the emission spectrum at different apertures is analyzed and it is found that the emission spectrum intensity is highest at 14-mm aperture. The molecular vibration stability and rotational temperature are obtained by fitting the emission spectrum. The vibrational temperature under small apertures is significantly higher than that under large apertures, while the rotational temperature remains relatively stable.