Experimental study on the effects of airflow, magnetic field and combination of airflow with magnetic field on nanosecond pulsed dielectric barrier discharge in atmospheric air

Abstract

An experimental study of the effects of airflow, magnetic field, and combination of airflow with magnetic field on a nanosecond pulsed dielectric barrier discharge (DBD) in atmospheric air is presented. The DBD is generated by an in-house designed DBD structure (a metal rod is inserted into the traditional parallel-plate DBD). The experimental results show that the application of airflow to the DBD can reinforce discharge and improve the discharge uniformity. When airflow increases to a certain velocity, surface discharge can transform into diffuse volume discharge. Moreover, the application of a magnetic field to DBD in static air can also enhance discharge, which is manifested as the enhancement of surface discharge. A similar but more significant effect is obtained in DBD combined airflow with magnetic field. Compared with the DBD with airflow only, the transition from surface discharge to diffuse volume discharge in DBD combined airflow with magnetic field occurs at a smaller airflow velocity. Besides, DBD combined airflow with magnetic field under different pulse repetition frequencies (PRFs) is also investigated. The results show that the minimum velocity required to generate diffuse volume discharge also shrinks with the decrease in PRF. In short, it is easier to generate diffuse volume discharge under the conditions of airflow, magnetic field, and lower PRF. The underlying physical mechanism of the above phenomena is discussed and mainly ascribed to the enhanced ionization by applying airflow, magnetic field, and lower PRF.