1) The presentation covered three projects: analyzing the impacts of the new Cryo-pump Divertor (CPD) on NSTX-U diagnostics, tracking the D-site water cooling system, and evaluating the PF-1C bus support structure. 2) For the CPD, each diagnostic bay was assessed to determine any interference from the new design. Some diagnostics would require redesigning to accommodate the CPD. 3) The water system was mapped to understand how contaminants could spread. 4) Structural analysis found the PF-1C bus support could withstand anticipated loads like torque and shear from magnetic field turbulence.

1. NSTX-U CPD DIAGNOSTIC IMPACTS, PF-1C BUS SUPPORT & D-SITE WATER SYSTEMS
Emmanuel O. Balogun, Kuishon A. Brown
Much Effort by: Neway Atnafu, Ron Bell, Andy Carpe, Robert Ellis, Steve Raftopoulos, Roger Raman, Matt Reinke, Filippo Scotti, Brent Stratton, John Winkelman, J. Mitchell, Stefan Gerhardt
Princeton Plasma Physics Laboratory, Princeton, NJ USA
INTRODUCTION
This presentation comprises three projects that were undertaken.
The Cryo-pump divertor (CPD) project is motivated by the need for a cryo-
pump and a re-design of the existing divertor in the NSTX-U. Port by port analysis
was done to see how the new CPD will affect respective diagnostics.
The second project is the D-Site Water Cooling System. Around Mid-July,
some contaminations were found in the water used for cooling the NSTX-U field
coils and thus we tracked down the cooling water system to find how the
contaminant might have been transported.
Finally, analysis work was done on the PF-1C Bus Support. The PF-1C Bus
Support is to provide support for the PF-1 Coils and preventing deflection of the
bus bars.
Final Presentation August 10th, 2016 • Princeton, NJ
SUMMARY TABLE OF FINDINGS
Analysis of Bays A & B viewing cones
CONCLUSION
Our work on the CPD diagnostics was instrumental in the success of the Conceptual Design review (CDR)
for the cryo-pumped divertor project. We were able to determine diagnostics that will be affected by the new
structure, and negotiate with physicists to redesign some structures to accommodate the new CPD.
Work on the D-Site water systems helped us create a flow diagram describing the water flow through a
central de-ionized make-up water system.
Structural analysis by hand calculations was done on the PF-1C bus flex cable support to test strengths in
both its parts and joints for anticipated loadings in the form of Torque, Shear, Tension, and Compression.
BAY DESCRIPTION FINDINGS
A PCHERS(Ron Bell), No interference with divertor detected so far.
Seems good.
B FIDA BKGRD(Deyoung Liu) No interference with divertor detected so far.
Seems good.
C U. Wash Bolometer; Dust Collector (Charles
Skinner/Raman)
Viewing cone of 70 degrees. Has extra-ion
outer shield, inner adapter, and lens is
straight up
D (Cryopump feedthroughs)
Future LD CP Feedthroughs
Not necessary; No interference
E EIES, VIPS (LLNL); Fast 1DCCD camera
(LLNL)
(Filippo Scotti)
Physicist will duplicate the specifications
from Bay H for this bay.
Interference is observed with the divertor and
the shield walls that are yet to be included in the
NSTX-U.
F QMB (Charles Skinner)
Elect. feedthroughs
Pending..
G UT-K Spectrometer, IR camera (Reinke) No interference with divertor detected so far.
Seems good.
H Visible fast camera(Filippo Scotti) Interference is observed with the divertor and
the shield walls that are yet to be included in the
NSTX-U.
I Elect. feedthroughs Not necessary.
J RF Probe (Bob Kaita)
Elect. feedthroughs
Okay. No interference detected.
K MAPP Probe, Elect. feedthroughs (Bob
Kaita)
Okay. No interference detected.
Bays A & B will continue to support the poloidal PCHERS
D-SITE WATER COOLING SYSTEMS FLOW CHART
Support is mounted to body of NSTX-U Machine
This work was made possible by funding from the Department of Energy for the Engineering Apprenticeship program.
PF1-C FLEX CABLES BUS SUPPORT
Above are pictures and drawings of the PF-1C Flex Cable Bus Supports. Hand calculations and
structural analysis was done to ensure it could withstand the forces caused by the turbulence of the
cables due to the presence of strong magnetic fields in NSTX-U. This structure is made almost
entirely out of stainless steel due to its insignificant magnetic permeability.
Tasked to identify the D-Site Water Systems Relationship with the
Facilities waters. Due to the fact that many drawings were either missing
or not up to date, extensive field work had to be undertaken.
Bays J and K Support Probe
• The present Bay I Upper
and Lower ports will support a
divertor resistive bolometer for
the FY17 & 18 runs.
• Elevated baffle top will
completely block the lower view.
• Need to assess the best path
forward after completing the CP
CDR.
– May involve a new
instrument at Bay I lower, tangential viewing bolometry,
viewing from the mid-plane.
Bay I Divertor Bolometer Is Severely Impacted by CP Design
Bays H & E Support Divertor Spectroscopy
• Evaluating the need to redesign the Bay H reentrant view and
shutter, given the raised divertor floor.
– Quite possible that the Bay E 1D CCD will need a similar
treatment.
• Must ensure lack of interference with divertor support structure.
Conceptual CAD model for diagnostic views
Above ore Images and picture of parts of the bus support
To the left is an image of hand
sketch-up of Bay G diagnostic
port views.
No pressing issues with views
were detected during sketch-up
Bay G
Above is an image of bay H port
showing diagnostic interference