Entwicklung eines Finite Elemente Verfahrens zur Modellierung der Plasmastroemung in der Randschicht von TOKAMAKS
Entwicklung eines Finite Elemente Verfahrens zur Modellierung der Plasmastroemung in der Randschicht von TOKAMAKS
Over the last years effort is increasing to employ Finite Element Methods for plasma edge fluid-modelling. Compared with commonly applied procedures, this method has the advantage, that not-simply-connected domains with complex geometrical structure can be described in detail. The purpose of the pre...
Saved in:
Personal Name(s): | Pütz, Thomas (Corresponding author) |
---|---|
Contributing Institute: |
Plasmaphysik; IEF-4 |
Imprint: |
Jülich
Forschungszentrum Jülich GmbH Zentralbibliothek, Verlag
1994
|
Physical Description: |
IV, 158 S. |
Document Type: |
Report |
Series Title: |
Berichte des Forschungszentrums Jülich
2942 |
Subject (ZB): | |
Link: |
OpenAccess |
Publikationsportal JuSER |
Over the last years effort is increasing to employ Finite Element Methods for plasma edge fluid-modelling. Compared with commonly applied procedures, this method has the advantage, that not-simply-connected domains with complex geometrical structure can be described in detail. The purpose of the presented work is to analyse these considerations and to develop a two-dimensional Finite-Element-Code. This code should be able to simulate the plasma flow pattern in the burning chamber of fusion devices by an exact and solution-dependent discretisation. Firstly the generalized Navier-Stokes-equations are modified according to the special features of the edge plasma. From these equations fundamental conditions for the applicability of the method can be derived. They are consistent with criteria found at other laboratories. Based on this, a numerically stable solution procedure is formulated. It is capable to deal with the strong anisotropy in plasma transport and the large velocity gradients arising in front of the limiter. Reionisation and other collision processes of recycled neutral particles are described by coupling the fluid model to the kinetic Monte-Carlo neutral-gas-code EIRENE. For comparison and fundamental numerical studies a fast analytical description of recycling is also available. Such rather crude approximations are employed in other codes often as the only option. By this, it is now possible to treat the flow of ions and neutral atoms/molecules near complex surface structures of fusion devices consistently. Because of the time step restriction in the special solution algorithm, up to now the electron temperature profile has to be provided from elsewhere. It can, for example be interpolated from experimental data or from results of other independent code calculations. The newly developed code is applied to a typical TOKAMAK-discharge (TEXTOR) and characteristic results are discussed. |