531. WE-Heraeus-Seminar: 3D versus 2D in Hot Plasmas

3D versus 2D in Hot Plasmas

Seminar
Datum:
Mo, 29.04.2013 17:00  –   Do, 02.05.2013 13:00
Adresse:
Physikzentrum Bad Honnef
Hauptstr. 5, 53604 Bad Honnef, Germany

Sprache:
Englisch
Veranstaltungspartner:
Wilhelm and Else Heraeus-Foundation
Kontaktperson:
Prof. Dr. Yunfeng Liang,

Beschreibung

Scope:
Currently, the most advanced concepts for fusion confinement are the tokamak and the stellarator. The former is toroidally symmetric and 2D; the latter is a 3D device with a smaller degree of symmetry. The tokamak scheme is currently a leading variant for plasma confinement and is therefore being used for the ITER design and is planned for the DEMO reactor. It has recently been realized that 3D effects also play a significant role in this 2D concept. Their influence can be seen in transport and energy confinement, in control of different magneto-hydrodynamic (MHD) instabilities and in the nature of disruption events.
Whether 3D effects have a positive or negative impact in terms of plasma confinement strongly depends on various parameters and needs to be investigated carefully. An example of a positive 3D effect is the mitigation/stabilization of dangerous Edge Localized Modes (ELMs) by the application of external 3D magnetic perturbations, which has been demonstrated in several tokamaks. It is now clear that the existence of these 3D effects brings tokamak and stellarator physics closer together and that these effects have to be addressed with a complex approach in order to gain the maximal benefit in terms of fusion performance.
3D effects form one of the hottest topics in fusion research today, and understanding them is essential for the success of future fusion devices. Thus, the collection of the most up-to-date theories and techniques, along with discussion between leading experts in the field, will be of great interest and scientific importance.
The 531. WEH Seminar is an attempt to discuss these 3D issues from all sides, bringing together experts from different devices (both tokamaks and stellarators) and from different fields (transport, fast particles, MHD instabilities, disruptions). It will build upon the success of the 480. WEH Seminar entitled “Active Control of MHD Stability” held in June 2011, which made it clear that 3D effects play a complex and crucial role in the control of plasma stability. However, this seminar will differ substantially from the previous one, which looked at integrating experimental methods to control MHD instabilities. Instead, the focus here is on the underlying physics of 3D effects on a much wider range of fields, which until recently has been neglected in tokamak research.
Discussing together and summarizing recent approaches will improve the physics understanding of various 3D effects on magnetically confined plasmas. In addition, comparing the advantages and disadvantages of 2D and 3D effects in hot plasmas will be beneficial and will guide the design of future fusion devices. Another major goal of this seminar is to give young scientists the opportunity to enter an active and growing field of research by interacting with world-leading experts.