Measurement of the positive streamer charge

Abstract

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The propagation of positive streamers in a weak and uniform background electric field

“…The extension of the region with a non-uniform electric field was less than 5% of the gap length. Such conditions were typical for the experiments presented in [9,11] where disc electrodes created a weak and uniform background electric field (figure 1). The local field enhancement took place close to the tip of the needle, which passed through a dielectric bushing placed in a hole in the centre of the anode.…”

“…The results of the experiments present amplitudes of the pure conductive current on a needle (solid curve) and the current measured on the cathode (broken curve) which includes both, conductive and A quantitative comparison between the experimental data presented in [11] and the simulations is presented in figure 7. The figure shows the mean linear charge density in one single streamer filament.…”

“…The value of E b depends on many factors, in particular on the humidity and the ambient temperature [7,10]. Moreover, at atmospheric pressure the streamer discharge is always observed as a number of filamentary channels even in short gaps [11]. It is obvious that this branching leads to a redistribution of the space-charge and also influences the conditions for streamer development.…”

“…The simulations were performed for the conditions corresponding to recent published experiments [9,11]. The experimental set-up is shown in figure 1, and consisted of a three-electrode arrangement.…”

Approche physique du développement de streamers positifs sur une surface de glace =

“…Pour les besoins de la simulation du champ, une conductivité surfacique 8 fois plus grande a été considérée. Des travaux ont déjà établi que le courant injecté à l'anode était un courant de conduction tandis que celui à la cathode était un courant capacitif ou un courant de déplacement associé à l'avancement du streamer [36,179]. Toutefois dés que le streamer arrive à la cathode, ce courant cathodique devient un courant de conduction.…”