August 11, 2011 FNAL Meeting Global Design Effort 1 DR-CFS Discussion Mark Palmer GDE

DR Layout (BTR version) August 11, 2011 FNAL Meeting Global Design Effort 2

Topics for Today Magnet System Heat Load Update Review of Tunnel Elements –Alcoves & Caverns –Cross Sections Miscellaneous Discussion and other Afternoon Discussion –Central Region Layout August 11, 2011 FNAL Meeting Global Design Effort 3

Heat Load Estimate Get away from % estimates of heat transferred to air vs water (depends on relative temperatures and affected surface areas). So attempt a better estimate as follows: 1.Convective heat transfer to air (non-forced): ~25W/m 2 /°C (high-end coeff. for non-forced case) where we need to consider the differential in temperature between the air and the avg magnet temperature 2.For non-cooled cables, treat full heat load as transferred to air Discuss on next 2 pages… August 11, 2011 FNAL Meeting Global Design Effort 4

Magnet Heat Loads Convective piece (ie, what fraction of magnet heat goes to air…) –Estimate 0.5m 2 of effective magnet surface area per ring per meter of length –Thus we can write: –So we have a ~25W/m convective contribution per ring for setting the air temp set point 2°C away from nominal water-based average temperature. –But don’t forget to include fixed piece… August 11, 2011 FNAL Meeting Global Design Effort 5

Contribution from Cables Rough estimate is that cable losses will likely be 5-10W/m per ring Note: all estimates based on arcs (region with highest conventional magnet load) Note: still need to do a full conceptual design update for the power supply system due to the significant changes in magnet strengths August 11, 2011 FNAL Meeting Global Design Effort 6

Overall Contribution Key assumptions: –Fixed water supply temperature everywhere in ring  this implies that the operating point in different regions of the ring will be slightly different –Convective estimate –Re-calculated cable loads based on new cable runs for the DTC lattice This suggests that we can hold the total heat load per ring to the W/m level as long as we have the control structure necessary to set the air temp in each section August 11, 2011 FNAL Meeting Global Design Effort 7

Comments? Would welcome any comments you might have on carrying out the updated analysis in this way… August 11, 2011 FNAL Meeting Global Design Effort 8

Alcoves and Caverns August 11, 2011 FNAL Meeting Global Design Effort 9

Alcove Locations RF cavern  OK 4 AORs  OK Alcoves to ELTR/PLTR  OK –Septa PSs can potentially go here –May need some straight ahead radiation protection from ELTR/PLTR lines Inj/Ext Straight PS alcoves need to be next to kickers between the ELTR and PLTR sections May need a bump-out at the end of the wiggler straight for a straight-ahead photon stop exiting through the first dipole. Need to discuss options for beam size monitor lines at some point August 11, 2011 FNAL Meeting Global Design Effort 10

Cross Sections Cornell designer (Joe Conway ) picking up Norbert’s designs Will allow considerably better cross-checking (and will look at a further reduction in beam line separation) with the new designs DTC01 – 2 arc cells August 11, 2011 FNAL Meeting Global Design Effort 11

Some Cross-Sections August 11, 2011 FNAL Meeting Global Design Effort 12

Miscellaneous Issues Ozone – primarily a wiggler region concern –Thermal jackets around VC – is there boil-off N 2 available to have a slow flow to prevent ozone build-up? Shaft size – Can we lower magnets already aligned on beams? August 11, 2011 FNAL Meeting Global Design Effort 13

Central Region Definitions Region A –Injection to and extraction from the DR e+ injection side –e+ injection septum 78.66m from centerline of DR »Angle1 =  x=0m »Angle2 = mrad  x=21.3m »End of  x=27.16m (  y=3.735m) –e- extraction septum 77.64m from centerline of DR »Angle1 =  x=0m »Angle2 = mrad  x=23.3m »End of  x=27.41 (  y=3.326m) August 11, 2011 FNAL Meeting Global Design Effort 14