Speaker
Gonzalo Rodríguez Prieto
Description
See the full Abstract at http://ocs.ciemat.es/EPS2018ABS/pdf/P1.4011.pdf
Initial studies on the morphology of the exploding wire plasma
G. Rodriguez Prieto1 , Malena Milanese2 , Luis Bilbao3
1 UCLM . ETSII, Ciudad Real, Spain
2 Intituto de Física Arroyo Seco, Tandil, Argentina
3 Universidad de Buenos Aires, Buenos Aires, Argentina
Exploding wire phenomenon consists initially in the transformation of a metallic wire matter
from solid to plasma state by a very intense, at least kA, and short, maximum of ns, electrical
current following through the wire in a controlled time.
Wire metal is initially heated by joule heating, which in turn transforms the wire into liquid,
metallic gas and finally a plasma that can still absorb part of the electrical energy [1]. The final
stage of the system, when the surrounding medium is atmospheric air, is a non expanded plasma
which shows diverse morphological instabilities, depending on the material and initial energy,
among other factors.
Electrical current distribution across the wire,
30
that could be approximated by a cylindrical one, W
Exp. Decay fitting
25 Pt
Exp. Decay fitting
cannot be considered as constant, or uniform, with a Fe
Exp. Decay fitting
20
large dependence on the skin depth of the material,
Counts
15
a parameter that indicates the penetration deep of
10
the electromagnetic fields inside the wire. In prin-
5
ciple, it is tempting to consider that such parame-
0
ter can be related with the final morphology of the 0 200 400 600 800 1,000
Length (px, A.U.)
plasma, as it sets up the initial condition for the
plasma expansion. In this work we show that such Figure 1: Distance distribution for the peaks
relation is not observed at a charging voltage of 20 and valleys of exploding wire plasmas.
kV, based on measurements of the distance between
observed peak and valleys, obtained with a fast frame camera synchronized with the exploding
wire. They can be adjusted to exponential decay functions with very similar fitted values for the
materials employed in these experiments. As fig. 1 shows, distribution of the distances between
consecutive peaks and valleys is very similar for the three metals used.
References
[1] G. Rodríguez Prieto, L. Bilbao, M. Milanese, Laser and Particle Beams 34, 263 – 269 (2016)
