论文信息 - β-Limiting MHD instabilities in improved-performance NSTX spherical torus plasmas - 字舞流文

β-Limiting MHD instabilities in improved-performance NSTX spherical torus plasmas

Global magnetohydrodynamic (MHD) stability limits in the National Spherical Torus Experiment (NSTX) have increased significantly recently due to a combination of device and operational improvements. First, more routine H-mode operation with broadened pressure profiles allows access to higher normalized β and lower internal inductance. Second, the correction of a poloidal field coil induced error-field has largely eliminated locked tearing modes during normal operation and increased the maximum achievable β. As a result of these improvements, peak β values have reached (not simultaneously) βT = 35%, βN = 6.4, βN = 4.5, βN/li = 10, and βP = 1.4. High βP operation with reduced tearing activity has allowed a doubling of discharge pulse-length to just over 1 s with sustained periods of βN≈6 above the ideal no-wall limit and near the with-wall limit. Details of the β-limit scalings and β-limiting instabilities in various operating regimes are described.

E. D. Fredrickson | R. E. Bell | Henry W. Kugel | C. H. Skinner | Rajesh Maingi | Franco Paoletti | Dan Stutman | D. W. Johnson | Yueng Kay Martin Peng | D. A. Gates | S. A. Sabbagh | E. J. Synakowski | Benoit P. Leblanc | Stanley M. Kaye | Stephan Paul | Jonathan Menard | R. J. Maqueda | Robert Kaita | D. W. Mueller | D. Stutman | R. Bell | B. Leblanc | E. Synakowski | D. Gates | H. Kugel | R. Kaita | E. Fredrickson | S. Sabbagh | M. Bell | S. Kaye | J. Menard | C. Bush | D. Johnson | R. Maingi | R. Maqueda | D. Mueller | M. Ono | F. Paoletti | Y. Peng | C. Skinner | R. Maqueda | S. Paul | Michael G. Bell | Charles E. Bush | Masayuki Ono | Morag Bell | J. Menard | S. Paul | Y-K. M. Peng | Y. Peng | B. LeBlanc | the NSTX Team | M. Ono | D. Johnson

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