HLRF Technical System Weekly Meeting

Thursday 16 Nov 2006, 03:00 → 05:00 US/Pacific

SLAC: SCS 115, 3-5PM PDT (High Level RF TS Review)

1. Review status of major HLRF subsystem, components in Baseline Conceptual Design. 2. Review progress of RDR Cost Modeling and Estimates, resource assignments, standard methodologies. 3. Review R&D progress for Alternate Conceptual Designs.

1 Agenda & Goals

Speaker: Raymond Larsen (SLAC)

document

• Corvin_comment_November_16__2006.msg
• Fw__HLRF_Meeting_of_Nov_15.msg
• HLRFCostModelOverview_070706_R3.pdf
• HLRF_Factory,_staging,_Installation_070706R3.pdf
• Sources_Electrical_Demand_vs_ML_15_NOV_2006.pdf

Slides

• HLRF_Agenda_Nov_16_2006.pdf
• HLRF_Agenda_Nov_16_2006.ppt
• HLRF_Cost_Update_110806R4.pdf
• ML_Heat_Load_Sep_18_2006A.pdf
• Pushback_ML_Criteria_Oct_2006.pdf

Attendees: KEK: S. Fukuda, M. Akemoto, H. Hayano FNAL: C. Jensen, M. Ball, J. Reid, O. Nezhevenko, M. Ross SLAC: C. Adolphsen, R. Cassel, K. Jobe, C. Nantista, R. Larsen The agenda and supporting documents are posted to the meeting website at: http://ilcagenda.cern.ch/conferenceDisplay.py?confId=1002 1. Valencia Update We discussed the cost review at Valencia and noted that the talk we gave is posted to the Indico HLRF meeting website. Supporting documentation of Factory and manpower estimates for costs other than acquisition costs is also posted. There were no major changes to the cost estimate, but we mentioned the proposed new ACD charger that might result in a cost benefit of about 2-3%. However other ACD efforts could potentially have much larger effect but these are not approved for the current estimating exercise. 2. S7 Task Force We also attended the first meeting of S7, the R&D Board Task Force headed by Terry Garvey for the purpose of ultimately coordinating and prioritizing the HLRF R&D programs for the GDE. Attendees besides Garvey were Fukuda, Hayano, Adolphsen, Solyak and Larsen. 3. Water-Fire-Air discussion The main entertainment was the revisiting of the power-to-air and cooling water requirements for the linac RF stations. The main points made during the discussion, in no particular order, were as follows: A. The main objective is to reduce the number of different water systems (Dirty (HCW), LCW and Chilled. It appears that most if not all systems that might use LCW do not really need it which eliminates a costly system including stainless plumbing. B. Only the instrument racks and possibly the modulator switch assemblies would use chilled water, for a total load of about 10 kW. C. The commercial racks planned are insulated with enclosed heat exchangers and virtually no heat radiating to air. The modulator itself could be repackaged in such racks to capture most of the heat now blown into air. D. The main step-down transformer, charger transformer and pulse transformer are all assumed to be oil-filled inside water cooled enclosures. These would have some radiant heating effect on surrounding air that would be hard to insulate. E. The klystron generates most of the heat for the station, about 75%, and will generate the most radiant heat to air. It could be insulated to some degree since it needs radiation shielding panels anyway. F. The waveguide system needs a temperature control of +/-2.5C. Stability, not absolute is important. The circulators, splitters and long WG runs need to be water cooled to this number. G. Circulator and load losses should be 29.8 kW vs. the 24.3 kW currently listed in Emil's table (Oleg). Also WG losses should be 5 kW vs. the 4 kW listed. H. Inlet water is assumed to be 95F for the 3-loop system and would drop to 90F for the two loop system. I. The tunnel temperature should be no more than 85F for habitation. J. The current klystron operation does not assume hyper evaporative (boiling) cooling but assumes a max outlet water temperature of 89C. K. Neubauer was supposed to have talked to vendors about maximum temperatures but was not present to report. L. We are unsure of the cooling requirements for the klystron solenoid but believe it does not need LCW. M. Tomski's current supply model is one LCW skid per 4 RF units. N. Chris Jensen will review the power loss numbers for the modulator power train and the LCW and chilled water requirements. O. Once the model is understood Keith Jobe will get together with Emil to refine the model and the table and come up with a realistic heat load to air while maintaining habitable tunnel air temperature. ***************************************** POST MEETING NOTES: Chris Jensen has communicated the following important factoids (I've slightly edited the following quotes): 1. The total heat load to LCW for each modulator is ~600 W (the main switch and bouncer switch). Requires flow of order 1 gpm if put both paths in series. The rest of the modulator and pulse transformer can be cooled with the rust inhibited water. 2. The total power (including the distribution power transformer from 34 kV to 480 V) for the charging supply was 11.5 kW. ...I had 7.5 kW for the 480V to 11 kVDC power supply and Clay had 4 kW for the 34 kV to 480 V transformer. The modulator was also 7.5 kW, so (we're) now up to 19 kW total charging supply and modulator. The pulse transformer I had listed as 6 kW (and it still is) but 5 kW is rise time loss which ends up in the klystron collector while 1 kW ends up in the pulse transformer..... So, we are at 20 kW for charging supply and modulator, not 15 kW. A reasonable actual estimate of heat to air could be done as follows: 1) The loss in the modulator is about 4 kW to air. All that could be trapped inside the modulator using insulated doors and removed with a air to water heat exchanger and the modulator cabinet would go ?? C above the water. This air temperature should be limited to 45 C (someone could argue a different temp) 2) The 12.5 kW remaining is in oil tanks with water cooling coils. A simple water cooling coil without pumping the oil would be a relatively low cost addition to any transformers (1k$ ??), but pumping the oil would cost more and incur pump maintenance for every transformer (not cheap). So with non pumped oil use a WAG of 10 C temperature difference (or a smart person who knows a real number) between water and oil. Then assume the tank is 10 C above ambient at the top of the tank and 0C above at the bottom. We have estimates for size of the tanks, so the surface area is known and a smart person (i.e. not me) could then estimate the heat load through the tank wall to ambient. 2b) a very similar thing can be done for the klystron solenoid (and maybe collector). They have large surface areas and radiate power to air based on water temp and delta T. 3) Using assumption from 1 and varying air temperature in 2 you could find how much power went to air with different air and water temps. That would give Marc something he could model and optimize to his satisfaction Chris ********************** Thank you Chris for the prompt response. I think the picture is quite clear now. Over to Keith and Emil for the next phase of the analysis. NEXT MEETING: In view of the 23rd being a holiday, the next regular meeting will be November 30th. Happy Holiday to all! Ray

2 KEK Progress

Speaker: Dr Shigeki Fukuda (KEK)

3 Main Linac & Klystron Status

Speaker: Chris Adolphsen (SLAC)

4 Distribution System Progress

Speaker: Dr Chris Nantista (SLAC)

5 Waveguide 3D Modeling

Speaker: Jerry Leibfritz

6 Distribution Costs

Speaker: Mike Neubauer (SLAC)

7 Modulator Progress

Speakers: Chris Jensen (FNAL), Clay Corvin (SLAC)

8 Controls/Interlocks/Protection Status

Speaker: Richard Cassel (SLAC)