ARIES Documents -- Meetings ArchiveARIES Conference Call, 18 October 2005
Documented by L. Waganer
It was mentioned the next meeting will be held in San Diego on November 17 (all day) and November 18 (half day) at UCSD. Jim Lyon noted that he would remain at UCSD for Friday afternoon so he can have more interaction with the ARIES team. A reminder: in order to prepare for the next meeting, all design parameters should be delivered to Jim Lyon on November 3, Thursday, so he will have adequate time to input a consistent set of reactor physics and engineering data.
Compact Stellarator Reactor Physics Basis
Physics and Coil Definitions of New Configurations and Divertor Definition
– TK Mau mentioned he and Long Poe Ku talked last week about the coil
definitions to be used for the coil structural analysis and divertor assessment.
There will be no new coil definition for the new reference NCSX ARE equilibrium.
The existing (old) NCSX coil set /equilibrium data are sufficiently close for
stress and divertor analyses. Likewise, the alpha particle exit points for ARE
can be mapped onto the old equilibrium. TK is working to define the divertor
topology. Rene Raffray is concerned about the high heat flux peaking around
20/1, which is unacceptable. A more reasonable value would be 6-7. Jim had sent
out the expected heat flux with peaking factors. Three options for reducing
the peak heat flux were discussed and all three should be evaluated to determine
if one or more might be used; 1) moving the divertor out with respect to the
LCMS, 2) use a radiative divertor, and/or 3) sweeping the narrow zone with the
peaked heat flux. The limiter option was excluded.
Compact Stellarator Reactor Engineering Assessment
Coil Structure Design and Analysis – Since the last conference call, several concepts for the coil structure were discussed. Xueren Wang has been defining the coil structure to resist the in-coil-plane and out-of-coil plane loads. His copy of NASTRAN is limited in size and cannot model the coil support structure with sufficient fidelity. ORNL has agreed to run a case to benchmark the lower fidelity UCSD analysis. We should consider the structural approach used in W7-X.
Blanket and Shield Neutronic Analysis - Laila El-Guebaly said she may have to increase the thickness of the shield-only zone by 20 cm to accommodate the manifolds. She will check if the reweldability requirement of the manifolds is met without additional shielding. Rene and Laila are working on the definition of the helium coolant access tubes. Rene said they are trying to recess the welds for better protection.
The move from HT to LT superconductor will impact the nuclear heating limit
and cryogenic heat load. Fluence could be the most stringent requirement, however.
Compact Stellarator Integrated Systems Assessment
Systems Code Analysis – Jim Lyon updated his systems code and obtained new results for the SOFE and Madrid conferences. He also supplied the latest results to the team as the most current data set, which Farrokh will post for reference.