Predictive analysis of high power ICRF heating in JET
2007 (English)In: RADIO FREQUENCY POWER IN PLASMAS , 2007, Vol. 933, 67-70 p.Conference paper (Refereed)
One aim of the 2007 JET shutdown is to increase the ICRF power by installing a new, internally matched, two-strap antenna and by adding external conjugate-T matching to two of the four A2 antennas for improved ELM-resilience. The new so-called ITER-like antenna is designed to deliver 7.2 MW to the plasma which, together with the A2 antenna improvements, effectively doubles the power available for ICRF heating. At the resulting power densities the resonant ion power partition, the collisional bulk plasma ion and electron heating fractions and profiles are all affected. With the increased power more resonant ions are accelerated to higher energies, leading to an increased electron heating fraction and, due to the wider ion orbits, broader heating profiles. The heating asymmetries with directed antenna spectra are enhanced, partly due to the higher power and thereby larger toroidal momentum transfer between wave and ions, and partly due to the reduced pitch-angle scattering of the higher-energy ions. Here, coupled wave field and resonant ion distribution function calculations are presented for JET Advanced Tokamak scenarios, where the low central current densities and associated broad fast ion orbits increase the impact of the power density, and analysed to determine to what extent the increased power density will affect the heating.
Place, publisher, year, edition, pages
2007. Vol. 933, 67-70 p.
, AIP Conference Proceedings
Fusion, Plasma and Space Physics
IdentifiersURN: urn:nbn:se:kth:diva-26176DOI: 10.1063/1.2800551ISI: 000251153300011ScopusID: 2-s2.0-36849011438OAI: oai:DiVA.org:kth-26176DiVA: diva2:372303
17th Topical Conference on Radio Frequence Power in Plasmas,Clearwater, FL, MAY 07-09, 2007
QC 201011252010-11-252010-11-192010-11-25Bibliographically approved