Empirical transport coefficients compared with quasi-linear fluctuation induced transport
Empirical scaling relations for the electron heat diffusivity, the diffusion coefficient and the inward drift velocity in the ohmic, L-and H-regimes of ASDEX are checked against anomalous transport predicted for electrostatic or magnetic fluctuations. It is stressed that the first two exhibit the same dependence on the fluctuation spectrum, which explains the coupling of these diffusivities observed in all confinement regimes. The values found for their ratios are shown to be general results of quasi-linear fluctuation induced transport and to agree with the empirical coefficients in the ohmic, L- and H-regimes. Also discussed are the consequences of proportional relationships for the interpretation of the saturated and improved ohmic confinement, and for the density profile shape.
Bibliographic Reference: Article: Nuclear Fusion, Vol. 30 (1990) No. 8, pp. 1610-1612
Record Number: 199011451 / Last updated on: 1994-12-02
Original language: en
Available languages: en