09 September SIT Meeting Summary

1. FY-03 Work Planning Process (Ron)
Planning input was received from WBS 1, 4, and 8.
ACTION: Ron issue reminders to WBS managers as needed to obtain remaining input, and schedule follow-up meetings to finalize plans and establish initial work authorizations.


2. Progress in critical configuration design tasks
Coil design: 3 cases of June vintage are now healed. They gain 2.2-2.6 cm in plasma-wall spacing. Adequacy of healing is being evaluated.
ACTION: Also assess adequacy of June designs against edge criteria. (Mike, edge group)


Structure time constants (Dave W.): Art Brooks is building a Spark model of the structure and will calculate eddy current time constants. First results expected in about a week.


3. Discussion of decision process for updating the configuration


Decisions needing to be made at the end of September have programatic as well as cost and schedule implications. Our baseline design is based on the M45 (unhealed) coil design. We need to update to a healed design that provides more plasma-wall clearance. The plan has been to adopt the best available design at the end of September. Is that still the right plan? There are two options:


Option 1: Adopt the best-available design at the end of September.
Option 2: Wait for recent designs, which provide better physics, to be healed and choose then.


Option 1:
Available designs are M45h and June designs, now healed. We would most likely choose one of the June designs, to get as much improvement in plasma-wall standoff as possible.
BENEFIT: Schedule: By choosing now, we would be able to have an updated CAD model by end of November, when negotiations for the modular coil R&D contracts are scheduled to start. It would keep us on schedule.
RISK: Programmatic: Plasma-wall standoff, though improved, still might not be enough for good edge physics performance (SOL, connection length).
RISK MITIGATION: Edge group take a closer look at the June designs in the next 2 weeks (before deciding) and assess adequacy.

Option 2:
BENEFIT: Programmatic: More plasma-wall standoff, so better physics performance and flexibility.
RISK: Schedule delay to complete healing. Mike expects healed cases could be available by end of October. If so, an updated model could be available by the end of December, about the time the R&D contracts are to be awarded. This would be only a one-month delay.
However, healing projections are typically uncertain, so it might take longer. If so, it would further impact the schedule. We would either have to delay the start of the R&D work, or possibly proceed with Phase I (planning and analysis) based on the current design and then shift to the new design for Phase II (prototype fabrication). The latter course is not favored by Engineering. There would be cost impacts, as well, which tend to increase the later a change is made.
Technical: Modified structure geometries of most recent recent designs are more uncertain than the June designs with respect to assembly problems. Won't know until a physical model is built.
Management: Until a new design is available, the project baseline is M45, which is uninteresting because it is not healed. It could raise concerns with the PAC and DOE.
RISK MITIGATION:
Schedule risk: Clearly explain the possibility of a downstream design change to the suppliers in the bid process and at the time the contract is being negotiated. Reach understanding of the likely impact and how it will be handled up front, avoiding surprises when the new design becomes available.
ACTION: Dave assess the cost and schedule impact of changing design between Phase I and II of the R&D contract.
Technical risk: Determine the get-well strategy now, in case assembly problems are encountered later.
Management risk: Explain these options, their risks and benefits, to DOE at next week's IPT meeting to get IPT involved in considering all the risks. ACTION: Hutch


4. Next SIT Meeting: Monday, Sept. 16 at 11:00 a.m. EDT (Wayne, chair).


5. Next IPT Meeting with DOE: Weds, Sept. 18 at 11:00 a.m. EDT. ACTION: Bob issue notice and agenda.


Summary by:
Hutch Neilson

Please forward any questions or comments to mailto:reiersen@pppl.gov

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