Direct simulations of turbulent transport in fusion devices : Emerging issuesFunded under: FP2-FUSION 10C
Direct numerical simulations have been used for more than a decade to study various reduced models of plasma dynamics. This paper is devoted to a summary of the contribution made by direct numerical simulations of fluid models to the present knowledge of the basic mechanisms of anomalous transport. In the first part of the work, the seemingly prevailing claim that numerical results are consistent with quasilinear theory is critically analysed employing general arguments of turbulence theory. Then the problem of the determination of the correlation length, the role of the coherent structures and the question of the subcritical transition to turbulence are addressed. Finally, the subtle role of dissipation is discussed: with the support of recent numerical results, and exploiting the analogy of some plasma turbulence models with those employed for ordinary fluids, it is argued that dissipation is likely to enter in a non-trivial way in the global scaling laws for plasma transport.
Bibliographic Reference: Report: JET-P(92)58 EN (1992) 25 pp.
Availability: Available from the Publications Officer, JET Joint Undertaking, Abingdon, Oxon. OX14 3EA (GB)
Record Number: 199211279 / Last updated on: 1994-11-29
Original language: en
Available languages: en