Numerical studies of confinement scaling in the conventional reversed field pinch
2000 (English)In: Nuclear Fusion, ISSN 0029-5515, E-ISSN 1741-4326, Vol. 40, no 11, 1885-1896 p.Article in journal (Refereed) Published
Scaling laws for reversed field pinch (RFP) confinement parameters versus plasma current and density are found from computer simulations. The RFP dynamics at high Lundquist numbers approaching 10(6) is studied using a high resolution, 3-D, resistive MHD numerical code. Optimum plasma conditions are attained by assuming that the transport coefficients are classical, and by ignoring radiation losses and resistive wall effects. Anomalous global transport results from classical parallel heat conduction along stochastic field lines in the plasma core. The pinch parameter is Theta = 1.8 and the aspect ratio is R/a = 1.25. Poloidal beta is found to scale as beta (theta) proportional to (I/N)(-0.40) I-0.40 and energy confinement time as tau (E) proportional to (I/N)(0.34) I-0.34. On-axis temperature scales as T(0) proportional to (I/N)(0.56) I-0.56. Experimental results from T2, RFX and MST agree well with the above numerical results and also with the obtained magnetic fluctuation scaling proportional to S-0.14, where S is the Lundquist number. Thus stochastic core field lines appear to persist also at higher, reactor relevant currents and temperatures in the conventional RFP, indicating the need to further pursue confinement enhancement techniques.
Place, publisher, year, edition, pages
2000. Vol. 40, no 11, 1885-1896 p.
poloidal current drive, energy confinement, particle-transport, fluctuations
IdentifiersURN: urn:nbn:se:kth:diva-20162DOI: 10.1088/0029-5515/40/11/308ISI: 000165343000008OAI: oai:DiVA.org:kth-20162DiVA: diva2:338855
QC 201005252010-08-102010-08-10Bibliographically approved