AA 559: Plasma Science Seminar

 Abstract:

A compact torus (CT) has a toroidal magnetic and plasma geometry, but is contained within a simply-connected vacuum vessel such as a cylinder.  Spheromaks and field-reversed configurations (FRCs) fall into this category. Compact tori are translatable and have a high engineering beta. The primary benefit of CTs for fusion is the absence of toroidal field (TF) and Ohmic Heating (OH) coils and the many problems brought on by them.  Studying fusion-relevant plasma in simply-connected geometries affords the world fusion program both physics and technology opportunities not found in other configurations.  

This talk outlines the technology and physics opportunities of compact tori, and presents a cost model based on geometry for comparison with less compact configurations. Technology opportunities are brought about by a simplified geometry, reduced cost due to omission of coils, and increased reliability and maintainability due to more easily demountable subsystems.  Without an externally imposed toroidal field, CT plasmas are stabilized either by appropriately tailoring the profile of currents flowing in the plasma or by the presence of a population of highly kinetic ions, allowing operation at high beta.  Formation and current drive are achieved by a variety of novel techniques involving magnetic reconnection that now are finding application for non-inductive start-up in larger machines.  CTs therefore also offer many unique opportunities for resolving critical issues relating to both technology and plasma physics, and serve as valuable test-beds for the development of new ideas.

Woodruff Scientific Inc was established to explore new ideas relating to CT current drive and heating.  A brief overview of the company, approach and projects will be given.

*Based on a recent collaborative white-paper by S. Woodruff, M. Brown, E. B. Hooper, R. Milroy, and M. Schaffer