Comparison of some turbulent confinement models for \hbox{DIII-D}, ARIES and FNSF

POSTER

Abstract

We give a detailed comparison of three of the leading turbulent confinement models applied to \hbox{DIII-D} and two advanced tokamak scenarios representing ARIES and FNSF. Of particular current interest is the recently installed Lehigh MMM7.1 transport module and its predictions compared to GLF23 and TGLF. A number of recent L- and \hbox{H-mode} \hbox{DIII-D} discharges are analyzed to check agreement with experiment for the three confinement models. The models can differ significantly in their predictions of tokamak confinement and, in particular, for steady state AT scenarios, the resulting rf current drive requirements can be somewhat different. For the AT cases, we show how fast wave on axis current drive together with ECH and \hbox{L-H} can be combined to produce favorable, negative shear $q$ profiles that have acceptable predicted (less than about 200~kA) residual ohmic current in steady state. The sensitivity of the results to particular distinguishing features of the confinement (e.g. drift resistive ballooning, and trapped electron modes) is examined.

Authors

  • H.E. St. John

    General Atomics

  • A.D. Turnbull

    General Atomics

  • M. Choi

    General Atomics

  • S.P. Smith

    General Atomics

  • L.L. Lao

    General Atomics, UKAEA, ASIPP

  • R.J. Buttery

    General Atomics