Plasma energy balance in the L-2M stellarator

Effect of ECRH regime on characteristics of short-wave turbulence in plasma of the L-2M stellarator

“…It is common knowledge that, in stellarators operating in currentless ECRH regime, the energy confinement time τ E scales with heating power P 0 as τ E ∝ P −0,59 0 in the ISS95 scaling and τ E ∝ P −0,58 0 in LHD scaling. A more expressed dependence τ E ∝ P −0,73 0 was observed for the L-2M stellarator in the range of plasma densities (0.5-2) × 10 13 cm −3 [1]. To explain anomalous transport, recent attention has been focused on short-wave turbulence associated with the ETG, ITG and TEM instabilities (see, e.g., [2][3][4]).…”

“…Degradation of the energy confinement time τ Е with an increase in heating power Р 0 in ECRH experiments is traced in well-known scalings: τ Е ∞ Р 0 -0,59 for the ISS95 and τ Е ∞ Р 0 -0,58 for LHD scaling. An even slower rise τ Е ∞ Р 0 -0,73 was observed for the L-2M stellarator in the range of plasma densities 0.5-2⋅10 13 cm -3 [1]. To explain anomalous transport, recent attention has been focused on short-wave turbulence associated with the ETG (Electron Temperature Gradient driven waves) instability (see, e.g., [2][3][4]).…”

“…The problem of interrelation between anomalous transport and characteristics of turbulence in toroidal magnetic confinement systems remains one of the central problems. Introduction of the anomalous thermal conductivity coefficient is critical in modeling transport processes in stellarators, especially in the edge plasma (see, e.g., [1][2][3]). Anomalous transport should be added to neoclassical transport to construct a model consistent with experiment.…”