Performance assessment of long-legged tightly-baffled divertor geometries in the ARC reactor conceptdoi:10.7910/DVN/NMVUFSHarvard Dataverse2020-06-031Michael Robert Knox Wigram, Brian LaBombard, Maxim V. Umansky, Adam Q Kuang, Theodore Golfinopoulos, Jim L. Terry, Daniel Brunner, Marvin E. Rensink, Christopher P. Ridgers, Dennis G. Whyte, 2020, "Performance assessment of long-legged tightly-baffled divertor geometries in the ARC reactor concept", https://doi.org/10.7910/DVN/NMVUFS, Harvard Dataverse, V1Performance assessment of long-legged tightly-baffled divertor geometries in the ARC reactor conceptdoi:10.7910/DVN/NMVUFSMichael Robert Knox Wigram, Brian LaBombard, Maxim V. Umansky, Adam Q Kuang, Theodore Golfinopoulos, Jim L. Terry, Daniel Brunner, Marvin E. Rensink, Christopher P. Ridgers, Dennis G. WhyteHarvard DataversePhysicsARCdetacheddivertormodellingpower handlingUEDGEExtremely intense power exhaust channels are projected for tokamak-based fusion power reactors; a means to handle them remains to be demonstrated. Advanced divertor configurations have been proposed as potential solutions. Recent modelling of tightly baffled, long-legged divertor geometries for the divertor test tokamak concept, ADX, has shown that these concepts may access passively stable, fully detached regimes over a broad range of parameters. The question remains as to how such divertors may perform in a reactor setting. To explore this, numerical simulations are performed with UEDGE for the long-legged divertor geometry proposed for the ARC pilot plant conceptual design - a device with projected heat flux power width (λq||) of 0.4 mm and power exhaust of 93 MW - first for a simplified Super-X divertor configuration (SXD) and then for the actual X-point target divertor (XPTD) being proposed. It is found that the SXD, combined with 0.5% fixed-fraction neon impurity concentration, can produce passively stable, detached divertor regimes for power exhausts in the range of 80-108 MW - fully accommodating ARC's power exhaust. The XPTD configuration is found to reduce the strike-point temperature by a factor of ~10 compared to the SXD for small separations (~1.4λq||) between main and divertor X-point magnetic flux surfaces. Even greater potential reductions are identified for reducing separations to ~1λq|| or less. The power handling response is found to be insensitive to the level of cross-field convective or diffusive transport assumed in the divertor leg. By raising the separatrix density by a factor of 1.5, stable fully detached divertor solutions are obtained that fully accommodate the ARC exhaust power without impurity seeding. To our knowledge, this is the first time an impurity-free divertor power handling scenario has been obtained in edge modelling for a tokamak fusion power reactor with λq|| of 0.4 mm.<a href="http://library.psfc.mit.edu/catalog/reports/2010/19ja/19ja020/abstract.php">PSFC REPORT PSFC/JA-19-20</a><br /><br />This work has been supported by the University of York, Massachusetts Institute of Technology (supported by US DoE cooperative agreement DE-SC0014264), Lawrence Livermore National Laboratory (supported under DoE Contract DE-AC52-07NA27344) and the UK Engineering and Physical Science Research Council (EPSRC) as part of the EPSRC Fusion Centre for Doctoral Training programme (under Training Grant Number EP/LO1663X/1).This dataset is made available without information on how it can be used. You should communicate with the Contact(s) specified before use.19ja020_archival_manuscript.pdfapplication/pdf