NUK - logo
Fakulteta za elektrotehniko, Ljubljana (FERLJ)
  • Estimating cross-field particle transport at the outer midplane of TCV by tracking filaments with machine learning [Elektronski vir]
    Han, Woonghee ...
    Cross-field transport of particles in the boundary region of magnetically confined fusion plasmas is dominated by turbulence. Blobs, intermittent turbulent structures with large amplitude and a ... filamentary shape appearing in the scrape-off layer (SOL), are known from theoretical and experimental studies to be the main contributor to the cross-field particle transport. The dynamics of blobs differs depending on various plasma conditions, including triangularity (δ). In this work, we analyze triangularity dependence of the cross-field particle transport at the outer midplane of plasmas with δ = +0.38, +0.15, −0.14, and −0.26 on the Tokamak `a Configuration Variable, using our novel machine learning (ML) blob-tracking approach applied to gas puff imaging data. The cross-field particle flux determined in this way is of the same order as the overall transport inferred from KN1D, GBS, and SOLPS-ITER simulations, suggesting that the blobs identified by the ML blob-tracking account for most of the cross-field particle transport in the SOL. Also, the ML blob-tracking and KN1D show a decrease in the cross-field particle transport as δ becomes more negative. The blob-by-blob analysis of the result from the tracking reveals that the decrease of cross-field particle transport with decreasing δ is accompanied by a decrease in the number of blobs in a fixed time, which tend to have larger area and lower radial speed. Also, the blobs in these plasmas are in the connected sheath regime, and show a velocity scaling consistent with the two-region model.
    Vir: Nuclear fusion [Elektronski vir]. - ISSN 1741-4326 (Vol. 63, no. 7, [article no.] 076025, Jul. 2023, 10 str.)
    Vrsta gradiva - e-članek ; neleposlovje za odrasle
    Leto - 2023
    Jezik - angleški
    COBISS.SI-ID - 192818179

    Povezava(-e):

    https://iopscience.iop.org/article/10.1088/1741-4326/acdae5

Vnos na polico