Study of possible key parameters for improved bulk transport of H-mode plasmas
The origin of the reduced electron heat diffusivity X(e) and the diffusion coefficient D in the core of H-mode plasmas is investigated. From the evolution of many local parameters in the L- and H-phases of ASDEX, it follows that only the density scale length r(n) is a possible key parameter. The r(n) values are larger in the H-phase, but the electron temperature scale lengths remain unchanged. A local transport law for X(e) and D, based on the increase of r(n), is tested by self-consistent transport simulations. It can be applied to ASDEX H-mode discharges with edge localised modes, but is incompatible with the broad density profiles observed in other devices.
Bibliographic Reference: Article: Nuclear Fusion, Vol. 30 (1990) No. 11, pp. 2377-2382
Record Number: 199110062 / Last updated on: 1994-12-02
Original language: en
Available languages: en