Effect of parallel magnetic field on repetitively unipolar nanosecond pulsed dielectric barrier discharge under different pulse repetition frequencies

Abstract

A magnetic field, with the direction parallel to the electric field, is applied to the repetitively unipolar positive nanosecond pulsed dielectric barrier discharge. The effect of the parallel magnetic field on the plasma generated between two parallel-plate electrodes in quiescent air is experimentally studied under different pulse repetition frequencies (PRFs). It is indicated that only the current pulse in the rising front of the voltage pulse occurs, and the value of the current is increased by the parallel magnetic field under different PRFs. The discharge uniformity is improved with the decrease in PRF, and this phenomenon is also observed in the discharge with the parallel magnetic field. By using the line-ratio technique of optical emission spectra, it is found that the average electron density and electron temperature under the considered PRFs are both increased when the parallel magnetic field is applied. The incremental degree of average electron density is basically the same under the considered PRFs, while the incremental degree of electron temperature under the higher-PRFs is larger than that under the lower-PRFs. All the above phenomena are explained by the effect of parallel magnetic field on diffusion and dissipation of electrons.

Magnetic field improves ozone production in an atmospheric pressure surface dielectric barrier discharge: understanding the physico-chemical mechanism behind low energy consumption

“…This phenomenon could be explained as follows. The introduced magnetic field magnetized electrons had a confinement effect on electrons through Lorentz force, 52 reducing the loss of high energy electrons. As a result, the proportion of electrons with high energy was increased together with the mean electron energy ε .…”

“…5 also supported this inference, where the ε increased by 0.1–0.3 eV (1 eV = 11604 K) after introducing the magnetic field, while the T g increased by only 10–20 K. The similar variation trends in ε and T g had also been reported by others. 28,52…”

Effect of external axial magnetic field on a helium atmospheric pressure plasma jet and plasma-treated water

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