C Cowley A Q Kuang D Moulton J D Lore J Canik M Umansky M Wigram S Ballinger B Lipschultz
The design and understanding of alternative divertor configurations may be crucial for achieving acceptable steady-state heat and particle material loads for magnetic confinement fusion reactors. Multiple x-point alternative divertor geometries such as Snowflakes and Xpoint targets have great potential in reducing power loads, but have not yet been…
PreprintC. Cowley Bruce Lipschultz David Moulton Ben Dudson
As tokamak research moves to reactor conditions, the control of a stable, optimally-detached divertor plasma has become increasingly relevant. Simple predictions of such detachment control have been performed previously using the Detachment Location Sensitivity (DLS) model of detachment. In this study the DLS model is extended and combined with SOL…
Preprint PublishedK. Verhaegh B. Lipschultz J.R. Harrison N. Osborne A. Williams P Ryan J. Allcock J. Clark F. Federici B. Kool T. Wijkamp A. Fil D. Moulton O. Myatra A. Thornton T.O.S.J. Bosman C. Bowman B. Duval S. Henderson R. Scannell the MAST Upgrade team the EuroFusion MST1 team
In this paper we a first qualitative analysis of the atomic and molecular processes at play during detachment in the MAST-U Super-X divertor, using divertor spectroscopy data. Our analysis indicates a wide operational regime of detachment of the MAST-U super-X divertor, which can be roughly separated in four phases: 1) The ionisation front detac…
PreprintA. Fil B. Lipschultz D. Moulton A. Thornton B. D. Dudson O. Myatra K. Verhaegh the EUROFusion WPTE team
MAST-U has recently started operating with a Super-X divertor, designed to increase total flux expansion and neutral trapping, both predicted through simple analytic models and SOLPS calculations to reduce the plasma and impurity density detachment thresholds. In this study, utilising the SOLPS-ITER code, we are quantifying the possible gain allowe…
Preprint PublishedJ. R. Harrison T. Farley G. M. Fishpool A. Kirk B. Lipschultz J. Lovell F. Militello D. Moulton P. Ryan R. Scannell A. J. Thornton K. Verhaegh L. Xiang
The benefits of an optimised Super-X divertor configuration in mitigating the steady-state power and particle fluxes to the surfaces of the MAST Upgrade divertor have been quantified by performing a detailed comparison with a conventional divertor for the first time. In otherwise identical plasmas with conventional and Super-X divertor configu…
PreprintK. Verhaegh B. Lipschultz J.R. Harrison B.P. Duval A. Fil D.S. Gahle D. Moulton O. Myatra A. Perek S. Henderson C. Theiler A. Thornton M. Wensing
This paper shows experimental results from the TCV tokamak that indicate plasma-molecule interactions involving D+2 and possibly D− play an important role as sinks of energy (through hydrogenic radiation as well as dissociation) and particles during divertor detachment if low target temperatures (< 3 eV) are achieved. Bot…
Preprint PublishedD. Russel J. Myra F. Militello D. Moulton
The 2D scrape-off-layer turbulence code (nSOLT) includes 1D Boltzmann neutral-plasma interactions, a model of divertor recycling (introduced here), and a fixed source of plasma concentrated at the core-side boundary. 1) Neutral injection in the far-SOL is accomplished by specifying the density of Franck-Condon distributed neutrals streaming in from…
Preprint PublishedL. Xiang F. Militello D. Moulton F. Subba L. Aho-Mantila D. Coster M. Wensing T. Lunt M. Wischmeier H. Reimerdes
The SOLPS-ITER simulations of European DEMO reactor, with 450 MW of power to be exhausted, show an increased operational space compared to the conventional single-null configuration. Using a reduced model with fluid neutrals and bundled impurities, we assessed the existence and the boundaries of operational space for DEMO with the conventional sing…
Preprint PublishedK. Verhaegh B. Lipschultz C. Bowman B.P. Duval U. Fantz A. Fil D. Moulton O. Myatra D. Wünderlich F. Federici D.S. Gahle J.R. Harrison A. Perek M. Wensing
Detachment, an important mechanism for reducing target heat deposition, is achieved through reductions in power, particle and momentum; which are induced through plasma-atom and plasma-molecule interactions. Experimental research in how those reactions precisely contribute to detachment is limited. Both plasma-atom as well as plasma-molecule intera…
Preprint PublishedF. Militello L. Aho-Mantila R. Ambrosino T. Body H. Bufferand G. Calabro’ G. Ciraolo D. Coster G. Di Gironimo P. Fanelli N. Fedorczak A. Herrmann P. Innocente R. Kembleton J. Lilburne T. Lunt D. Marzullo S. Merriman D. Moulton A. Nielsen J. Omotani G. Ramogida H. Reimerdes M. Reinhart P. Ricci F. Riva A. Stegmeir F. Subba W. Suttrop P. Tamain M. Teschke A. Thrysoe W. Treutterer S. Varoutis M. Wensing A. Wilde M. Wischmeier L.Y. Xiang
A thorough physics and engineering analysis of alternative divertor configurations is carried out by examining benefits and problems by comparing the baseline single null solution with a Snowflake, an X- and a Super-X divertor. It is observed that alternative configurations can provide margin and resilience against large power fluctuations, but the…
Preprint Purchase