Abstract Details
Abstracts
Author: Benjamin D Dudson
Requested Type: Poster
Submitted: 2026-03-20 15:39:54
Co-authors: T. Ashton-Key, M. Kryjak
Contact Info:
Lawrence Livermore National Laboratory
7000 East Avenue
Livermore, CA 94550
USA
Abstract Text:
BOUT++/Hermes-3 provides predictive simulations of plasma profiles and particle and heat fluxes in the SOL and divertor in X-point geometry, without requiring ad-hoc cross-field diffusion coefficients. The only inputs are the magnetic geometry, total power across the separatrix and particle fueling rate. Simulations of the TCV-X21 reference L-mode case show good agreement with experiment across a wide range of measurements [1]. The Hermes-3 model has since been extended to include electromagnetic flutter terms and applied to the SPARC double null PRD 20221013. Using P_SOL=10MW, core fueling of 4×10^21/s and no neutral recycling a simulation was run for 2.5ms to reach approximate steady state. The resulting separatrix density is 5e19 m-3, electron temperature ~500eV. These preliminary simulations predict an OMP heat flux width of λ_q∼0.35mm, spreading factor S ~ 0.12mm. Simulations require approximately 1 week per ms, using one node (128 cores) on Perlmutter with a grid resolution of 128 (radial) x 32 (parallel) x 81 (toroidal). Future directions include the addition of neutral gas and impurity radiation effects, to provide insights into the interaction of plasma cross-field transport and divertor power dissipation.
[1] B. Dudson et al. 2026 Nucl. Fusion 66 036015 doi:10.1088/1741-4326/ae3627
This work was in part performed under the auspices of the U.S. DoE by LLNL under Contract DE-AC52-07NA27344. Supported by Fusion Energy Sciences Theory & Modeling (SCW0229).
Characterization: 2.0
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