BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Memento EPFL//
BEGIN:VEVENT
SUMMARY:Physics basis for the ITER  tungsten divertor
DTSTART:20190219T103000
DTEND:20190219T113000
DTSTAMP:20260407T053530Z
UID:ef7fe65fb3e9444421b10818bc5dbf9e15366ef042c8feef8b463c77
CATEGORIES:Conferences - Seminars
DESCRIPTION:Dr. Richard A. Pitts\, ITER Organization\, St-Paul-lez-Durance
 \, France\nThe first ITER tungsten (W) divertor is the largest and most co
 mplex of its kind ever to be constructed. It must survive an expected ~200
 0 hours of plasma exposure through the non-active to the first DT campaign
 s. A key parameter determining the operational range for stationary loadin
 g is the peak target power flux density\, qpk\, itself fixed by the allowa
 ble surface temperature to remain below W recrystallization. There is a st
 rong relationship between qpk and the divertor neutral pressure\, pn\, the
  latter crucial for adequate He exhaust during burning plasmas. The main d
 ivertor design features were established using a database generated with t
 he SOLPS code\, which found an acceptable operational range within the con
 straints fixed by the input assumptions. However\, some of the latter requ
 ire modification in the light both of recent improvements in the physics m
 odel and the need for divertor component shaping. All tend to push the ope
 rating space to higher pn and higher concentration of extrinsic impurities
  with increased upstream densities. Nevertheless\, there appears to be suf
 ficient margin to avoid the deep detachment often associated with operatio
 nal limits in today‘s devices. Analysis of the state-of-the-art knowledg
 e of expected ELM transient amplitudes on the divertor targets\, the compu
 ted ELM ion orbit loading profiles on the shaped component edges and mater
 ial surface fatigue effects strongly indicate that ITER must achieve essen
 tially complete ELM mitigation during baseline fusion power operation.\n 
LOCATION:ppb019
STATUS:CONFIRMED
END:VEVENT
END:VCALENDAR