Recycling source terms for edge plasma fluid models and impact on convergence behaviour of the BRAAMS B2 code
Predictive simulations of tokamak edge plasmas require the most authentic description of neutral particle recycling sources. Employing a prototypical ITER divertor arrangement under conditions of high recycling, trial calculations with the BRAAMS B2 steady-state edge plasma transport code, plus varying approximations of recycling, reveal marked sensitivity of both results and convergence behaviour to details of sources incorporated. Comprehensive EIRENE Monte Carlo resolution of recyling is implemented by full and short intermediate cycles between the plasma fluid and statistical neutral particle models. As generally for coupled differencing and stochastic procedures, overall convergence properties become more difficult to assess. A pragmatic criterion for the B2/EIRENE code system is proposed to determine its success, proceeding from a stricter condition previously identified for one particular analytic approximation of recycling in B2. Certain procedures are also inferred potentially to improve their convergence further.
Bibliographic Reference: Report: EN (1994) 70 pp.
Availability: Available from Zentralbibliothek der Forschungszentrum Jülich GmbH, Postfach 1913, 5170 Jülich (DE)
Record Number: 199411263 / Last updated on: 1994-11-25
Original language: en
Available languages: en