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- Rasch, Joel, 1982, et al.
(författare)
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Gas breakdown in inhomogenous microwave electric fields
- 2009
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Ingår i: Journal of Physics D: Applied Physics. - 1361-6463 .- 0022-3727. ; 42:20, s. 205203-
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Tidskriftsartikel (refereegranskat)abstract
- The main physical properties of gas breakdown in inhomogeneous high frequency microwave electric fields are investigated using both analytical and numerical analysis. In particular, the interplay between diffusion and attachment in redistributing electrons from high field regions to low field regions and the concomitant effect on the breakdown threshold is studied using three different examples of ionization profiles. The results give a clear physical picture of the dependence of breakdown electric field on pressure showing a high pressure branch determined by conditions in the high field region, a low pressure branch determined by the properties of the low field region only, and a more or less smooth transition region for intermediate pressures. Simple estimates for the extension of the transition region are given in good agreement with the numerical simulations, and a comparison of the theoretical breakdown threshold with previous experimental results also shows good agreement.
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| 2. |
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| 3. |
- Rasch, Joel, 1982, et al.
(författare)
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Microwave Corona Breakdown in rf Devices
- 2009
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Ingår i: Progress in Electromagnetics Research Symposium (PIERS), August 18-21, 2009, Moscow, Russia, PIERS Proceedings, Moscow Russia, The Electromagnetics Academy, Cambridge, MA, USA. ; , s. 1228-1231
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Konferensbidrag (refereegranskat)
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| 4. |
- Rasch, Joel, 1982, et al.
(författare)
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Microwave Corona Breakdown in Strongly Inhomogeneous Fields
- 2009
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Ingår i: 36th European Physical Society Conference on Plasma Physics 2009, EPS 2009; Sofia; Bulgaria; 29 June 2009 through 3 July 2009. - 9781622763368 ; 33E, s. 657-660
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Konferensbidrag (refereegranskat)abstract
- We investigate the main physical properties of microwave corona breakdown in strongly inhomogeneous electric fields. The focus is put on numerical and approximate analytical calculations of the breakdown threshold in an exponential ionization profile, which is the basic form of the ionization profile caused by the field enhancement around irregular and curved conducting objects. The breakdown threshold is a value associated with a certain plasma density profile. We explain the major characteristics of the density profile, its dependance on pressure and the interplay of diffusion and attachment. For lower pressures the diffusion distributes the electrons from regions of high ionization frequency to regions of weak ionization, where the attachment acts as a sink. For high pressures the diffusion becomes negligible and the breakdown threshold is set by the equality of the ionization and attachment frequencies in the high field region.
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| 6. |
- Semenov, V. E., et al.
(författare)
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Multipactor breakdown in waveguide irises
- 2009
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Ingår i: 2009 IEEE International Vacuum Electronics Conference, IVEC 2009; Rome; Italy; 28 April 2009 through 30 April 2009. - 9781424434992 ; , s. 321-322
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Konferensbidrag (refereegranskat)abstract
- A detailed analysis is made in order to establish the multipactor breakdown threshold in wave guide irises. The analysis involves an analytical investigation based on the conformal mapping technique and also extensive numerical simulations. Comparison with recent experimental results shows good agreement. The main goal of the work is to obtain multipactor charts for the iris, i.e. the breakdown voltage as a function of the frequency - gap product, for different height to width ratios of the iris.
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