Transport and fluctuations in high temperature spheromak plasmasa)
| dc.contributor.author | McLean, H. S. | |
| dc.contributor.author | Wood, R. D. | |
| dc.contributor.author | Cohen, B. I. | |
| dc.contributor.author | Hooper, E. B. | |
| dc.contributor.author | Hill, D. N. | |
| dc.contributor.author | Moller, J. M. | |
| dc.contributor.author | Romero-Talamás, Carlos | |
| dc.contributor.author | Woodruff, S. | |
| dc.date.accessioned | 2024-01-24T10:54:37Z | |
| dc.date.available | 2024-01-24T10:54:37Z | |
| dc.date.issued | 2006-05-08 | |
| dc.description.abstract | Higher electron temperature (Tₑ>350 eV) and reduced electron thermal diffusivity (Xₑ < 10 m²/s) is achieved in the Sustained Spheromak Physics Experiment (SSPX) by increasing the discharge current = I gun and gun bias flux = Ψ gun in a prescribed manner. The internal current and q = safety factor profile derived from equilibrium reconstruction as well as the measured magnetic fluctuation amplitude can be controlled by programming the ratio λ gun =μ₀Igun / Ψ gun. Varying λ gun above and below the minimum energy eigenvalue = λ FC of the flux conserver (Δ x B = λ FC B) varies the q profile and produces the m/n = poloidal/toroidal magnetic fluctuation mode spectrum expected from mode-rational surfaces with q=m/n. The highest Tₑ is measured when the gun is driven with λ gun slightly less than λ FC, producing low fluctuation amplitudes (<1%) and 1/2<q<2/3. Transport analysis shows a reduction in Xₑ as Tₑ increases, differing from Bohm or open field line transport models where Xₑ increases with Tₑ. Detailed resistive magnetohydrodynamic simulations with the NIMROD code support the analysis of energy confinement in terms of the causal link with the q profile, magnetic fluctuations associated with low-order mode-rational surfaces, and the quality of magnetic surfaces | |
| dc.description.sponsorship | This work was performed under the auspices of the U.S. DOE by the University of California Lawrence Livermore National Laboratory under Contract No. W-7405-ENG-48. | |
| dc.description.uri | https://pubs.aip.org/aip/pop/article-abstract/13/5/056105/1032750/Transport-and-fluctuations-in-high-temperature?redirectedFrom=fulltext | |
| dc.format.extent | 9 pages | |
| dc.genre | journal articles | |
| dc.identifier.citation | H. S. McLean, R. D. Wood, B. I. Cohen, E. B. Hooper, D. N. Hill, J. M. Moller, C. Romero-Talamas, S. Woodruff; Transport and fluctuations in high temperature spheromak plasmas. Phys. Plasmas 1 May 2006; 13 (5): 056105. https://doi.org/10.1063/1.2192469 | |
| dc.identifier.uri | https://doi.org/10.1063/1.2192469 | |
| dc.identifier.uri | http://hdl.handle.net/11603/31471 | |
| dc.language.iso | en_US | |
| dc.publisher | AIP | |
| dc.relation.isAvailableAt | The University of Maryland, Baltimore County (UMBC) | |
| dc.relation.ispartof | UMBC Mechanical Engineering Department Collection | |
| dc.rights | This work was written as part of one of the author's official duties as an Employee of the United States Government and is therefore a work of the United States Government. In accordance with 17 U.S.C. 105, no copyright protection is available for such works under U.S. Law. | |
| dc.rights | Public Domain Mark 1.0 | en |
| dc.rights.uri | https://creativecommons.org/publicdomain/mark/1.0/ | |
| dc.title | Transport and fluctuations in high temperature spheromak plasmasa) | |
| dc.type | Text | |
| dcterms.creator | https://orcid.org/0000-0002-6830-3126 |