Dynamics of streamer propagation in air

Abstract

Results concerning the dynamics of streamer propagation in air under a uniform electric field are presented and discussed. Experiments were performed in a plane-parallel electrode arrangement with positive streamers initiated at a sharp point in the earthed anode. The basic properties of streamers are described in terms of the electric field required for a stable propagation and the associated propagation velocity. Critical parameters are the ambient electric field, the voltage used for streamer initiation and the distance of traverse. The present experiments permit the separation between the effects of the above parameters upon streamer advancement and propagation over the whole path up to the cathode. It is shown that an intrinsic propagation field with an associated velocity can be defined, which determine the propagation of streamers of a limiting, minimum energy. The propagation velocity is a power function of the electric field and, with the aid of an empirical equation, values can be expressed accurately in terms of these intrinsic streamer properties.

Monte Carlo simulation of corona discharge in SF6

“…The propagation velocity of the ionization front is in the range of 3 × 10 7 to 4 × 10 7 cm/s. We find that the calculated values for the frontal velocities agree well with the experimental results [21][22][23] and with those reported in [20,[24][25][26][27]. Measurements [21,22] of the average propagation velocity of the ionization front extend from 2 × 10 7 to 5 × 10 7 cm/s, the propagation average velocity [24,25] of the ionization wave is approximately of 5 × 10 7 cm/s, which agrees with our results.…”

The simulation of streamer dynamics in the air gap

“…However, when the pulse duration is below the certain value, the impact ionization is week, therefore, the streamer may stop some place in the gap. Allen found that long pulse duration also caused low stability propagation field E st in the experiment [4].…”

“…The experiment on steamer dynamics is based on the 3-electrode arrangement [4] which consists of two paralleled plane electrodes with a gap clearance of about 12cm, as figure 1 shows. The upper plane is applied with a variable negative voltage, while the nether plane is grounded, establishing a quasi-uniform electric field between the two planes.…”

“…It is helpful for understanding the air gap breakdown to study the streamer dynamics, which also has important significance on design and operation of transmission lines and electrical equipment. Investigators have put great efforts to the research of streamer propagation dynamics during air gap breakdown, and got many achievements [1][2][3][4], however, seldom researches on the effect of atmospheric parameters.…”

“…The experiment on steamer dynamics is based on the 3-electrode arrangement [4]. Positive streamer was initiated by application of a positive square pulse on the needle.…”