Characteristics of the global energy confinement and central pressure in LHD

J. Miyazawa, H. Yamada, R. Sakamoto, H. Funaba, K. Y. Watanabe, S. Sakakibara, K. Ida, M. Goto, T. Morisaki, S. Murakami, Inagaki Shigeru

Research output: Contribution to journalArticle

10 Citations (Scopus)

Abstract

Global energy confinement in the Large Helical Device has been proved to be comparable to those of tokamaks in ELMy H-mode. It shows a gyro-Bohm-like property as seen in international stellarator scalings. This implies that the anomalous transport dominates the neoclassical transport. At least in the configurations with small helical ripples, no significant collisionality dependence predicted by the neoclassical theory has been observed. Confinement degradation compared with the international stellarator scalings often takes place in the plasmas with high peripheral density. In many cases, this is due to the shallow penetration of heating beams. Adding to this, deviation from gyro-Bohm can be caused by the emergence of a "weak temperature dependence" of the thermal dijfusivity. It depends on the plasma parameters whether this weak temperature dependence deteriorates or improves the thermal transport. The central pressure that is also an important parameter for envisioning a fusion reactor is not necessarily proportional to the global confinement. The central pressure is insensitive to the variation of magnetic configuration that strongly affects the global confinement.

Original languageEnglish
Pages (from-to)29-37
Number of pages9
JournalFusion Science and Technology
Volume58
Issue number1
DOIs
Publication statusPublished - Jan 1 2010

Fingerprint

Plasmas
stellarators
Fusion reactors
scaling
Heating
Degradation
Temperature
temperature dependence
energy
fusion reactors
configurations
ripples
penetration
degradation
deviation
heating
Hot Temperature

All Science Journal Classification (ASJC) codes

  • Civil and Structural Engineering
  • Nuclear and High Energy Physics
  • Nuclear Energy and Engineering
  • Materials Science(all)
  • Mechanical Engineering

Cite this

Miyazawa, J., Yamada, H., Sakamoto, R., Funaba, H., Watanabe, K. Y., Sakakibara, S., ... Shigeru, I. (2010). Characteristics of the global energy confinement and central pressure in LHD. Fusion Science and Technology, 58(1), 29-37. https://doi.org/10.13182/FST10-A10790

Characteristics of the global energy confinement and central pressure in LHD. / Miyazawa, J.; Yamada, H.; Sakamoto, R.; Funaba, H.; Watanabe, K. Y.; Sakakibara, S.; Ida, K.; Goto, M.; Morisaki, T.; Murakami, S.; Shigeru, Inagaki.

In: Fusion Science and Technology, Vol. 58, No. 1, 01.01.2010, p. 29-37.

Research output: Contribution to journalArticle

Miyazawa, J, Yamada, H, Sakamoto, R, Funaba, H, Watanabe, KY, Sakakibara, S, Ida, K, Goto, M, Morisaki, T, Murakami, S & Shigeru, I 2010, 'Characteristics of the global energy confinement and central pressure in LHD', Fusion Science and Technology, vol. 58, no. 1, pp. 29-37. https://doi.org/10.13182/FST10-A10790
Miyazawa J, Yamada H, Sakamoto R, Funaba H, Watanabe KY, Sakakibara S et al. Characteristics of the global energy confinement and central pressure in LHD. Fusion Science and Technology. 2010 Jan 1;58(1):29-37. https://doi.org/10.13182/FST10-A10790
Miyazawa, J. ; Yamada, H. ; Sakamoto, R. ; Funaba, H. ; Watanabe, K. Y. ; Sakakibara, S. ; Ida, K. ; Goto, M. ; Morisaki, T. ; Murakami, S. ; Shigeru, Inagaki. / Characteristics of the global energy confinement and central pressure in LHD. In: Fusion Science and Technology. 2010 ; Vol. 58, No. 1. pp. 29-37.
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