Comfinement optimization by plasma shaping on TCV
Any improvement in the energy confinement time of a tokamak reactor may facilitate its access to ignition. TCV has the unique capability of creating a wide variety of plasma shapes and can therefore investigate to which extent an appropriate choice of the plasma shape can improve the energy confinement time. For simple shapes defined only by their elongation and triangularity, it has already been observed on TCV that the confinement properties of the plasma depend strongly on the shape. This previous work has now been extended to include more complex shapes and higher elongations, in order to test the applicability of the previously proposed explanation for the shape dependence of the confinement time and also to propose new shapes which offer a substantial gain on their confinement characteristics. No influence of the plasma shape on the transport mechanism has been found for the explored shapes and operational regimes. Global energy confinement can however be considerably improved by plasma shaping. Study of the influence of a high order shape parameter, such as the squareness, shows that even if engineering of physical constraints may restrict the choice of the basic shape parameters, there remains room for a substantial gain in the confinement properties with an appropriate shaping.
Bibliographic Reference: Article: Proceedings of 24th EPS Conference on Controlled Fusion and Plasma Physics, Berchtesgaden 9-13 June 1997, pp. 529-532
Record Number: 199810025 / Last updated on: 1998-02-03
Original language: en
Available languages: en