Pedestal Characteristics of H-Mode Plasmas in JT-60U and ASDEX Upgrade

Search this Article

Author(s)

Abstract

The role of the pedestal structure in ELMy H-mode plasmas for the core energy confinement and for the ELM energy losses were investigated in two tokamak-type devices, JT-60U and ASDEX Upgrade. The confinement degradation seen at higher densities is attributed to the reduction of the pedestal temperature limited by the ELM activities and the stiffness of the temperature profiles. In high triangularity or impurity seeded H-modes, in which higher energy confinement is generally achieved, a higher pedestal temperature is obtained by improving the edge MHD stability or the density profile peaking, respectively. The upper bound of the ELM energy loss is characterized by the pedestal energy. The ELM energy loss can become smaller at fixed pedestal energy when the pedestal collisionality is raised. Raising the pedestal collisionality also enhances the inter-ELM perpendicular transport loss and reduces the ELM loss power fraction. In ASDEX Upgrade, the continuous pellet injection is shown to effectively mitigate ELM losses while preserving the core confinement quality. In JT-60U, the operation regime of grassy ELM is investigated and shown to achieve highly integrated performance of high energy confinement with small ELMs in the low collisionality regime.

Journal

  • Journal of Plasma and Fusion Research

    Journal of Plasma and Fusion Research 81(4), 280-287, 2005-04-25

    The Japan Society of Plasma Science and Nuclear Fusion Research

References:  31

  • <no title>

    ZOHM H.

    Plasma Phys. Control. Fusion 38, 105, 1996

    Cited by (10)

  • <no title>

    ZOHM H.

    Plasma Phys. Control. Fusion 38, 1213, 1996

    Cited by (3)

  • <no title>

    CONNOR J. W.

    Plasma Phys. Control. Fusion 40, 191, 1998

    Cited by (2)

  • <no title>

    CONNOR J. W.

    Plasma Phys.Control.Fusion 40, 531, 1998

    Cited by (3)

  • <no title>

    WADE M. R.

    Nucl. Fusion 38, 1839, 1998

    Cited by (2)

  • <no title>

    AYMAR R.

    Nucl. Fusion 42, 519, 2002

    Cited by (1)

  • <no title>

    ITER Physics Basis Expert Groups on Divertor and Divertor Modelling and Database

    Nucl. Fusion 39, 2391, 1999

    Cited by (1)

  • <no title>

    LOARTE A.

    Fusion Energy 2000 (Proc. 18th Int. Conf. Sorrent, 2000), 2000

    Cited by (1)

  • <no title>

    JET Team

    Nucl. Fusion 39, 1687, 1999

    Cited by (1)

  • <no title>

    SUTTROP W.

    Fusion Energy 1998 (Proc. 17th Int. Conf. Yokohama, 1998) 2, 777, 1999

    Cited by (1)

  • <no title>

    ASAKURA N.

    Plasma Phys.Control.Fusion 39, 1295, 1997

    Cited by (4)

  • <no title>

    TAKIZUKA T.

    Plasma Phys. Control. Fusion 40, 851, 1998

    Cited by (3)

  • <no title>

    URANO H.

    Nucl. Fusion 42, 76, 2002

    Cited by (2)

  • <no title>

    SUTTROP W.

    Plasma Phys. Control. Fusion 39, 2051, 1997

    Cited by (5)

  • <no title>

    URANO H.

    Plasma Phys. Control. Fusion 44, 11, 2002

    Cited by (2)

  • <no title>

    URANO H.

    J. Plasma Fusion Res. (SERIES), 239, 2001

    Cited by (1)

  • <no title>

    URANO H.

    Plasma Phys. Control. Fusion 44, A437, 2002

    Cited by (2)

  • <no title>

    URANO H.

    Plasma Phys. Control. Fusion 45, 1571, 2003

    Cited by (1)

  • <no title>

    LANG P. T.

    Nucl. Fusion 44, 665, 2004

    Cited by (1)

  • <no title>

    LANG P. T.

    Nucl. Fusion 36, 1531, 1996

    Cited by (2)

  • <no title>

    JACKSON G. L.

    Phys. Rev. Lett. 67, 3098, 1991

    Cited by (7)

  • <no title>

    BAYLOR L. R.

    Phys. Plasmas 7, 878, 2000

    Cited by (1)

  • <no title>

    URANO H.

    Plasma Phys. Control. Fusion 46, A315, 2004

    Cited by (1)

  • <no title>

    KAMADA Y.

    Plasma Phys. Control. Fusion 44, A279, 2002

    Cited by (2)

  • <no title>

    BOSCH H. S.

    J. Nucl. Mater. 266-269, 462, 1999

    Cited by (1)

  • <no title>

    SAKASAI A.

    J.Nucl.Mater. 266-269, 312, 1999

    Cited by (3)

  • <no title>

    GROTH M.

    Nucl. Fusion 42, 591, 2002

    Cited by (1)

  • <no title>

    LEONARD A.

    J. Nucl. Matter. 266-269, 109, 1999

    Cited by (5)

  • <no title>

    JANESCHITZ G.

    J. Nucl. Matter. 290-293, 1, 2001

    DOI  Cited by (3)

  • <no title>

    BAYLOR L. R.

    J. Nucl. Mater. 290-293, 398, 2001

    Cited by (1)

  • <no title>

    TAKENAGA H.

    Phys. Plasmas 8, 2217, 2001

    DOI  Cited by (3)

Codes

  • NII Article ID (NAID)
    110006281929
  • NII NACSIS-CAT ID (NCID)
    AN10401672
  • Text Lang
    ENG
  • Article Type
    ART
  • ISSN
    09187928
  • NDL Article ID
    7346387
  • NDL Source Classification
    ZM35(科学技術--物理学)
  • NDL Call No.
    Z15-8
  • Data Source
    CJP  NDL  NII-ELS  J-STAGE  NDL-Digital 
Page Top