Suppression of first-wall interaction in negative triangularity plasmas on TCV
Abstract
Magnetically confined fusion plasmas with negative triangularity (d) exhibit greater L-mode confinement than with positive d. Recent experiments in the TCV and DIII-D tokamaks have correlated the confinement improvement to a reduction of fluctuations within the plasma core. We report on fluctuation measurements in the scrape-off layer (SOL) for −0.61 < d < +0.64 in limited and diverted ohmic L-mode plasmas; these reveal a strong reduction in SOL fluctuation amplitudes at d < −0.25, and, surprisingly, an almost full suppression of plasma interaction with the main-chamber first-wall, which could have important implications for the prospects of using negative d plasmas as a reactor solution. An exploration of several physical mechanisms suggests that a reduced connection length—intrinsic to negative d plasmas—plays a critical role in the origin of this phenomenon.
- Authors:
- Publication Date:
- DOE Contract Number:
- SC0014264; SC0020327; SC0010529
- Research Org.:
- Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States). Plasma Science and Fusion Center; Univ. of California, San Diego, CA (United States)
- Sponsoring Org.:
- USDOE Office of Science (SC), Fusion Energy Sciences (FES)
- Subject:
- 70 PLASMA PHYSICS AND FUSION TECHNOLOGY
- OSTI Identifier:
- 1887946
- DOI:
- https://doi.org/10.7910/DVN/JOMOQF
Citation Formats
Han, W., Offeddu, N., Golfinopoulos, T., Theiler, C., Tsui, C. K., Boedo, J. A., and Marmar, E. S. Suppression of first-wall interaction in negative triangularity plasmas on TCV. United States: N. p., 2022.
Web. doi:10.7910/DVN/JOMOQF.
Han, W., Offeddu, N., Golfinopoulos, T., Theiler, C., Tsui, C. K., Boedo, J. A., & Marmar, E. S. Suppression of first-wall interaction in negative triangularity plasmas on TCV. United States. doi:https://doi.org/10.7910/DVN/JOMOQF
Han, W., Offeddu, N., Golfinopoulos, T., Theiler, C., Tsui, C. K., Boedo, J. A., and Marmar, E. S. 2022.
"Suppression of first-wall interaction in negative triangularity plasmas on TCV". United States. doi:https://doi.org/10.7910/DVN/JOMOQF. https://www.osti.gov/servlets/purl/1887946. Pub date:Wed May 11 00:00:00 EDT 2022
@article{osti_1887946,
title = {Suppression of first-wall interaction in negative triangularity plasmas on TCV},
author = {Han, W. and Offeddu, N. and Golfinopoulos, T. and Theiler, C. and Tsui, C. K. and Boedo, J. A. and Marmar, E. S.},
abstractNote = {Magnetically confined fusion plasmas with negative triangularity (d) exhibit greater L-mode confinement than with positive d. Recent experiments in the TCV and DIII-D tokamaks have correlated the confinement improvement to a reduction of fluctuations within the plasma core. We report on fluctuation measurements in the scrape-off layer (SOL) for −0.61 < d < +0.64 in limited and diverted ohmic L-mode plasmas; these reveal a strong reduction in SOL fluctuation amplitudes at d < −0.25, and, surprisingly, an almost full suppression of plasma interaction with the main-chamber first-wall, which could have important implications for the prospects of using negative d plasmas as a reactor solution. An exploration of several physical mechanisms suggests that a reduced connection length—intrinsic to negative d plasmas—plays a critical role in the origin of this phenomenon.},
doi = {10.7910/DVN/JOMOQF},
journal = {},
number = ,
volume = ,
place = {United States},
year = {2022},
month = {5}
}
Works referencing / citing this record:
Suppression of first-wall interaction in negative triangularity plasmas on TCV
journal, February 2021
- Han, W.; Offeddu, N.; Golfinopoulos, T.
- Nuclear Fusion, Vol. 61, Issue 3