Advanced surrogate model for electron-scale turbulence in tokamak pedestals
| dc.contributor.author | Farcas, Ionut-Gabriel | en |
| dc.contributor.author | Merlo, Gabriele | en |
| dc.contributor.author | Jenko, Frank | en |
| dc.date.accessioned | 2025-02-10T19:38:05Z | en |
| dc.date.available | 2025-02-10T19:38:05Z | en |
| dc.date.issued | 2024-10-28 | en |
| dc.description.abstract | We derive an advanced surrogate model for predicting turbulent transport at the edge of tokamaks driven by electron temperature gradient (ETG) modes. Our derivation is based on a recently developed sensitivity-driven sparse grid interpolation approach for uncertainty quantification and sensitivity analysis at scale, which informs the set of parameters that define the surrogate model as a scaling law. Our model reveals that ETG-driven electron heat flux is influenced by the safety factor q, electron beta βe and normalized electron Debye length λD, in addition to well-established parameters such as the electron temperature and density gradients. To assess the trustworthiness of our model’s predictions beyond training, we compute prediction intervals using bootstrapping. The surrogate model’s predictive power is tested across a wide range of parameter values, including within-distribution testing parameters (to verify our model) as well as out-of-bounds and out-of-distribution testing (to validate the proposed model). Overall, validation efforts show that our model competes well with, or can even outperform, existing scaling laws in predicting ETG-driven transport. | en |
| dc.description.version | Published version | en |
| dc.format.extent | 21 page(s) | en |
| dc.format.mimetype | application/pdf | en |
| dc.identifier | ARTN 905900510 (Article number) | en |
| dc.identifier.doi | https://doi.org/10.1017/S0022377824001314 | en |
| dc.identifier.eissn | 1469-7807 | en |
| dc.identifier.issn | 0022-3778 | en |
| dc.identifier.issue | 5 | en |
| dc.identifier.uri | https://hdl.handle.net/10919/124556 | en |
| dc.identifier.volume | 90 | en |
| dc.language.iso | en | en |
| dc.publisher | Cambridge University Press | en |
| dc.rights | Creative Commons Attribution 4.0 International | en |
| dc.rights.uri | http://creativecommons.org/licenses/by/4.0/ | en |
| dc.subject | plasma instabilities | en |
| dc.subject | fusion plasma | en |
| dc.subject | plasma simulation | en |
| dc.title | Advanced surrogate model for electron-scale turbulence in tokamak pedestals | en |
| dc.title.serial | Journal of Plasma Physics | en |
| dc.type | Article - Refereed | en |
| dc.type.dcmitype | Text | en |
| dc.type.other | Article | en |
| dc.type.other | Journal | en |
| pubs.organisational-group | Virginia Tech | en |
| pubs.organisational-group | Virginia Tech/Science | en |
| pubs.organisational-group | Virginia Tech/Science/Mathematics | en |
| pubs.organisational-group | Virginia Tech/All T&R Faculty | en |
| pubs.organisational-group | Virginia Tech/Science/COS T&R Faculty | en |