Erratum: “Equations and improved coefficients for parallel transport in multicomponent collisional plasmas: Method and application for tokamak modeling” [Phys. Plasmas 28, 062308 (2021)]

In the SOLPS-ITER code, the same temperature is assumed for all ion species (⁠ $Ti$⁠). Therefore, the ion heat flux $h¯α$ can be written as follows: $h¯α=∑ZZ2hαZ/Zα2¯$⁠. For the single charge state ions, $h¯α=h¯α*$⁠. Thus, for plasmas with single charge state main ions and multi-charge state impurity ions, the total plasma heat-dependent part of the viscous-stress tensor $π↔ih=∑α,Zπ↔αZh$ is mainly defined by the heat fluxes of the single charge state main ion species, for which $h¯α=h¯α*$⁠. For impurities, the friction and thermal forces dominate the parallel momentum balance, and the changes due to $(∇·π↔αZ(par))∥$ for impurities due to $h¯α≠h¯α*$ do not lead to substantial changes in the impurity transport. As a result, no substantial changes are expected for the most common plasma mixtures used in magnetic fusion device simulations, such as hydrogen isotope plasma with impurities.

To confirm this, tests were performed using a D+T+N mixture in the ASDEX-Upgrade H-mode with the SOLPS-ITER code, including the Zhdanov–Grad module, drifts, and currents. As expected, correcting $h¯α→h¯α*$ in Eq. (44) in Ref. 1 led to only minor changes in the solution. Despite the minor impact on the SOLPS-ITER solution, it is important to consider this correction for implementing the multi-species heat flux-dependent part of the viscous-stress tensor in future fluid models.