Recent progress in the ARIES compact stellarator study

An integrated study of compact stellarator power plants, ARIES-CS, was initiated recently to explore attractive compact tellarator configurations and to define key R&D areas. Optimization of any stellarator configuration represents a large number f trade-offs among physics parameters and engineering constraints. As such, the ARIES-CS study was divided into three phases. he first phase was devoted to initial exploration of physics and engineering options, requirements, and constraints. In the second hase, we explored the configuration space for compact stellarators, aiming at configurations that satisfy physics/engineering onstraints. This paper summarizes our work to date. We have identified several promising quasi-axisymmetric configurations, ll aimed at low plasma aspect ratios and compact size. In each case, trade-offs among plasma parameters (e.g., -particle loss ersus ) were explored. Modular coils were designed to examine the geometric complexity and the constraints of the maximum eld, desirable coil-plasma and coil-coil spacing, etc. Our examination of engineering options is reported here. In particular, we nd that by employing “shield-only” zones in strategic areas, the minimum plasma-coil distance can be reduced by ∼40%. This pproach, together with the relatively low aspect ratio of quasi-axisymmetric stellarators leads to devices which are similar in ize to advanced tokamak power plants. 2006 Elsevier B.V. All rights reserved.