Role of isotopes in microturbulence from linear to saturated Ohmic confinement regimes

Autor: Lei Qi, Jae-Min Kwon, T. S. Hahm, M. Leconte, Sumin Yi, Y. W. Cho, Janghoon Seo
Jazyk: angličtina
Rok vydání: 2024
Předmět:
Zdroj: Physical Review Research, Vol 6, Iss 1, p L012004 (2024)
Druh dokumentu: article
ISSN: 2643-1564
DOI: 10.1103/PhysRevResearch.6.L012004
Popis: The first-principle gyrokinetic numerical experiments investigating the isotopic dependence of energy confinement achieve a quantitative agreement with experimental empirical scalings, particularly in Ohmic and L-mode tokamak plasmas. Mitigation of turbulence radial electric field intensity |δE_{r}|^{2} and associated poloidal δE×B fluctuating velocity with the radial correlation length l_{cr}∝M_{i}^{0.11} strongly deviating from the gyro-Bohm scaling is identified as the principal mechanism behind the isotope effects. Three primary contributors are classified: the deviation from gyro-Bohm scaling, zonal flow, and trapped electron turbulence stabilization. Zonal flow enhances isotope effects primarily through reinforcing the inverse dependence of turbulence decorrelation rate on isotope mass with ω_{c}∝M_{i}^{−0.76}, which markedly differs from the characteristic linear frequency. The findings offer insights into isotope effects, providing critical implications for energy confinement optimization in tokamak plasmas.
Databáze: Directory of Open Access Journals