Speaker
Description
The well-known two-point model [1, 2, 3] is a simple way to connect midplane and target conditions in the SOL. To further connect parallel and perpendicular SOL transport, average radial diffusive and advective transport of particles and heat is often assumed. However, the radial transport in the SOL is turbulent, consisting of plasma filaments of excess particles and heat driven by interchange motion [4]. This turbulence gives rise to correlations between fluctuations not accounted for when considering average plasma parameters [3].
Recent progress in stochastic modeling of filaments has resulted in self-consistent expressions for both single-point fluctuations and radial profiles due to filamentary transport [4, 5], giving expressions consistent with experimental measurements [6, 7]. In this contribution, we extend the stochastic model to simultaneous models for particle density and temperature as well as perpendicular particle and heat fluxes. We compare the results to expectations from diffusion-advection models for the simple SOL [1], and consider the effect of including the filamentary transport on target conditions.
References
[1] P. C. Stangeby. “The Plasma Boundary of Magnetic Fusion Devices.” CRC Press, 2000.
[2] F. Militello. “Boundary Plasma Physics.” Springer, 2023.
[3] W. Fundamenski. “Power exhaust in Fusion Plasmas.” CUP, 2009.
[4] O. E. Garcia et al. Phys. Plasmas 23.5 (2016). doi: 10.1063/1.4951016.
[5] J. M. Losada, A. Theodorsen, and O. E. Garcia. Phys. Plasmas 30 (2023).
doi: 10.1063/5.0144885.
[6] S. Ahmed et al. Plasma Phys. Controlled Fusion 65.10 (2023). doi:
10.1088/1361-6587/acf2c1.
[7] O. E. Garcia et al. “Blob structures and density shoulder formation in Alcator C-Mod”. Oral contribution at TTF 2025.