Spatial–temporal evolution of plasma radiation in electrical wire explosion: a morphological observation. (8th June 2020)

• Record Type: Journal Article
• Authors: Han, Ruoyu; Zhu, Wanying; Wu, Jiawei; Li, Chen; Zhang, Chenyang; Cui, Ruilin; He, Feng; Ouyang, Jiting; Wang, Yanan; Ding, Weidong
• Is Part Of: Journal of physics. Volume 53:Number 34(2020)
• Publication Date: 2020-06-08
• Subjects: electrical explosion of a wire -- metal plasma -- optical emission -- shock wave -- plasma ignition; Physics -- Periodicals; 530
• DOI: 10.1088/1361-6463/ab8b07
• Languages: English
• ISSNs: 0022-3727

Abstract

Abstract: This paper deals with an experimental study regarding the spatial–temporal evolution of single wire explosions in air and water at atmospheric pressure. Experiments were carried out with a microsecond timescale pulsed current source under 500 J stored energy. The morphology of the exploding wire with different discharge type, wire material, insulating coat, and ambient medium was intensively observed via self-emission images. The results revealed that the plasma radiation of wire explosion in air mainly contained two stages: initial intense radiation from optically thick plasma, and later decaying radiation from expanded arc-like plasma. A hollow structure was observed in a Cu exploding wire in air, and the plasma channel tended to develop inside it. As for W case, there would always be a core-corona structure, resulting in lower expansion rate and shock wave strength. Moreover, the plasma radiation of the underwater wire explosion was mainly determined by two factors: expansion rate and chemical reaction. The expansion rate of the radiant region in water was only 10 –1 mm μ s –1 level (1 mm μ s –1 level for air), leading to the lagging radiation. No noticeable difference in morphology was found between Cu and W wire explosions in water. Particularly, the Al wire explosion generated a bright light emission due to chemical reactions. Finally, radiative characteristics in an exploding wire were preliminarily concluded and existing problems proposed.