The two-mesh grid refinement method for the B2 code

We introduce version 6.0 of the 2D multispecies plasma fluid code 132, to which a flexible dynamic grid adaptation module has been added. The method followed in this paper involves the creation of two grid structures. A fine 2D mesh produced from the magnetic flux surface structure serves as a scaffolding on which a rougher, adaptable mesh is constructed depending on the physical situation. The conditions for grid refinement/coarsening involve normalized gradients of the plasma parameters. The algorithm and its numerical implementation are described in detail. As a sample application, the detachment behaviour of an ASDEX-Upgrade L- Mode discharge has been studied. A comparison of the results from the old and new B2 code versions is presented. Similar results in the overall plasma behaviour are seen but differences appear in the detachment zone, due to the grid adapting to the strong local gradients. Increased (decreased) gas puffing leads to an upward (downward) shift of the detachment front as well as to a shift of the zone of maximum grid density. The now code allows one to increase the grid density in the zone of interest without a strong increase CPU runtime, thus enabling a more realistic modelling of the detachment front

The two-mesh grid refinement method for the B2 code

We introduce version 6.0 of the 2D multispecies plasma fluid code 132, to which a flexible dynamic grid adaptation module has been added. The method followed in this paper involves the creation of two grid structures. A fine 2D mesh produced from the magnetic flux surface structure serves as a scaffolding on which a rougher, adaptable mesh is constructed depending on the physical situation. The conditions for grid refinement/coarsening involve normalized gradients of the plasma parameters. The algorithm and its numerical implementation are described in detail. As a sample application, the detachment behaviour of an ASDEX-Upgrade L- Mode discharge has been studied. A comparison of the results from the old and new B2 code versions is presented. Similar results in the overall plasma behaviour are seen but differences appear in the detachment zone, due to the grid adapting to the strong local gradients. Increased (decreased) gas puffing leads to an upward (downward) shift of the detachment front as well as to a shift of the zone of maximum grid density. The now code allows one to increase the grid density in the zone of interest without a strong increase CPU runtime, thus enabling a more realistic modelling of the detachment front

Improved modelling of detachment and neutral-dominated regimes using the SOLPS B2-Eirene code

In this paper, recent progress in plasma edge modelling is presented, using the SOLPS B2-Eirene Scrape-Off Layer Plasma Simulation code. The code capabilities have been extended so that is it now possible to investigate reliably regimes dominated by strong neutral sources in the plasma edge. Two main improvements are reported. First, a fluid plasma treatment including drift and currents effects has been coupled to a Monte-Carlo treatment for the neutrals. Concurrently, a grid adaptation algorithm compatible with the coupling is demonstrated. We present simulations taking advantage of these new tools, and discuss their impact on the results. (C) 2003 Elsevier Science B.V. All rights reserved

Further developments of the edge transport simulation package, SOLPS

The development of the SOLPS suite of codes (B2-Eirene + others) in the last two years is covered. Important issues are: the determination of the anomalous radial transport directly from the experiment, as well as by coupling to turbulence codes; the extension of the drift & current model in B2, and new results for the L-H transition; the development of a new version of B2 including grid refinement; some modelling results on compression and in/out target asymmetry

Further developments of the edge transport simulation package, SOLPS

The development of the SOLPS suite of codes (B2-Eirene + others) in the last two years is covered. Important issues are: the determination of the anomalous radial transport directly from the experiment, as well as by coupling to turbulence codes; the extension of the drift & current model in B2, and new results for the L-H transition; the development of a new version of B2 including grid refinement; some modelling results on compression and in/out target asymmetry