Ecton processes in vacuum arc
- Inst. of Electrophysics, Ekaterinburg (Russian Federation)
It is established that when microexplosions occur on a cathode there is a so-called explosive electron emission (EEE) observed. Such an emission is realized through individual short portions (the electron avalanches) which we have named {open_quotes}ectons{close_quotes}. The duration of electron current of such a portion is dictated by the time needed to cool down the emission center, that causes the EEE to stop. We will proceed from the assumption of Kesaev, that the cathode spot consists of separate cells from which the current i{sub n}, equal to the doubled arc current i{sub m}, is flowing. An ecton is formed by interaction between the liquid metal stream and plasma. When the current exceeds a certain threshold value, the liquid metal stream produces a drop. This drop, even before its break-off, leads to the increase in density of the ion current from plasma in the stream-drop joint. This results in a great energy concentration in the joint and initiates an ecton due to the Joule heating of the joint. We consider the arc cycle to consist of two processes. The first one, of a duration t{sub e}, is the process of ecton operation. The second one, of a duration t{sub i}, is due to the ion current flowing within the cathode region. During the t{sub i} period the formation of a new liquid metal stream is completed, which causes a new ecton to emerge. The process thus becomes self-sustaining. If the new ecton is produced, with a drop breaking-off, then the criterion for the arc cycle to be self-sustaining is written as {gamma}d{sup t}i{sub m} {ge} 1.
- OSTI ID:
- 226889
- Report Number(s):
- CONF-950749-; TRN: 96:001471-0026
- Resource Relation:
- Conference: 22. international conference on phenomena in ionized gases, Hoboken, NJ (United States), 31 Jul - 4 Aug 1995; Other Information: PBD: 1995; Related Information: Is Part Of XXII International conference on phenomena in ionized gases. Contributed papers 1; Becker, K.H.; Carr, W.E.; Kunhardt, E.E. [eds.]; PB: 172 p.
- Country of Publication:
- United States
- Language:
- English
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