Study of the confinement properties in a reversed-field pinch with mode rotation and gas fuelling

QC 20100524
An extensive investigation of the global confinement properties in different operating scenarios in the rebuilt EXTRAP T2R reversed-field pinch (RFP) experiment is reported here. In particular, the role of a fast gas puff valve system, used to control plasma density, on confinement is studied. Without gas puffing, the electron density decays below 0.5 x 10(19) M-3. The poloidal beta varies between 5% and 15%, decreasing at large I/N. The energy confinement time ranges from 70 to 225 mus. With gas puffing, the density is sustained at n(e) approximate to 1.5 x 10(19) m(-3). However, a general slight deterioration of the plasma performances is observed for the same values of I/N: the plasma becomes cooler and more radiative. The poloidal beta is comparable to that in the scenarios without puff but the energy confinement time drops ranging from 60 to 130 mus. The fluctuation level and the energy confinement time have been found to scale with the Lundquist number as S-0.05+/-0.07 and S0.5+/-0.1, respectively. Mode rotation is typical for all the discharges and rotation velocity is observed to increase with increasing electron diamagnetic velocity.

NATURVETENSKAP Fysik Atom- och molekylfysik och optik hsv//swe
NATURAL SCIENCES Physical Sciences Atom and Molecular Physics and Optics hsv//eng
POLOIDAL CURRENT DRIVE
ENERGY CONFINEMENT
RFX
FLUCTUATIONS
VUV
Atomic and molecular physics
Atom- och molekylfysik

Ingår i:Plasma Physics and Controlled FusionBRISTOL, ENGLAND : IOP PUBLISHING LTD44:8, s. 1625-16380741-33351361-6587

Av författaren/redakt...: Cecconello, Marc ...; Malmberg, Jenny- ...; Nielsen, P; Pasqualotto, R; Drake, James Rob ...

Om ämnet

Kungliga biblioteket hanterar dina personuppgifter i enlighet med EU:s dataskyddsförordning (2018), GDPR. Läs mer om hur det funkar här.
Så här hanterar KB dina uppgifter vid användning av denna tjänst.