Positive and negative streamers in ambient air: modelling evolution and velocities

By Alejandro Luque, V. Ratushnaya, Ute Ebert. 2008

257 citations recorded by the source corpus.

We simulate short positive and negative streamers in air at standard temperature and pressure. First, double-headed streamers in homogeneous electric fields of 50 kV cm−1 are briefly studied, and then we analyse streamers that emerge from needle electrodes with voltages of 10–20 kV in more detail. The streamer velocity at a given streamer length depends only weakly on the initial ionization seed, except in the case of negative streamers in homogeneous fields. We characterize the streamer evolution by length, velocity, head radius, head charge and maximal field enhancement. We show that the velocity of positive streamers is determined mainly by their radius and in quantitative agreement with recent experimental results both for radius and velocity. The velocity of negative streamers is dominated by electron drift in the enhanced field; in the low local fields of the present simulations, it is little influenced by photo-ionization. Initially it is puzzling that negative streamers can be slower than positive ones under similar conditions, both in experiment and in simulation, as negative streamer fronts always move at least with the electron drift velocity in the local field. We argue that this drift motion broadens the streamer head, decreases the field enhancement and ultimately leads to slower propagation or even extinction of the negative streamer.

Subfields: Electrical and Electronic Engineering, Radiology, Nuclear Medicine and Imaging

View Paper: https://www.semanticscholar.org/paper/d3327e966a190e60e482bf1fb422202f2e488430

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Electrical and Electronic Engineering

1. S. Nijdam
2. Ute Ebert
3. Alejandro Luque
4. Van Veldhuizen
5. Chao Li
6. E. V. Veldhuizen
7. T. Briels
8. Jannis Teunissen

In Radiology, Nuclear Medicine and Imaging

1. S. Nijdam
2. Ute Ebert
3. Alejandro Luque
4. Van Veldhuizen
5. E. V. Veldhuizen
6. T. Briels
7. Chao Li
8. Jannis Teunissen

Citations in the corpus

• Probing photo-ionization: experiments on positive streamers in pure gases and mixtures (2009, background): “While negative streamers naturally propagate through electron drift (possibly supported by additional mechanisms), positive streamers are typically easier to generate, but more difficult to explain [13], as they propagate against the electron drift direction with velocities comparable to this veloci”
• Review of recent results on streamer discharges and discussion of their relevance for sprites and lightning (2010, background): “Several streamers and their interactions up to now have been studied in only three papers [Naidis, 1996; Luque et al., 2008a, 2008b]; they are discussed in section 3.3.1.”
• Positive streamers in air and nitrogen of varying density: experiments on similarity laws (2008, background): “) Note that the velocities are related to the diameters [24, 39, 40].”