1. LHCb-UT and Velo Upgrade Road to a system EDR in Q4-2015 8 June 2015 Bart Verlaat 1

2. Summary of the requirements LHCb-UT –Expected dissipation: 5kW –Required cooling temperature range: +20 / -35 ⁰ C –Mass flow required: ⁰ C TBC, current estimate 64g/s @ VQ=0.25 –Pressure head required: TBC, reasonable budget=> 15 bar dP@-35 ⁰ C LHCb-Velo Upgrade –Expected dissipation: 1.8kW –Required cooling temperature range: +20 / -30 ⁰ C –Mass flow required: TBC, current estimate 23g/s @ VQ=0.25 –Pressure head required: TBC, reasonable budget => 15 bar dP@-30 ⁰ C –Safety system to avoid vacuum vessel over pressurization Missing requirements The TBC’s listed depends on the ongoing and future evaporator tests and designs (Full loop behavior including distribution restrictions) 2

3. Road to the EDR (1) 3 Requirements Safety system Transfer line concept Plant concept design Requirements Evaporator concept and performance Transfer line concept Redundancy concept P&ID FA Engineering Design Review Velo UT Evaporator concept and performance

4. Road to EDR (2) There is enough detail known to start thinking about the system concept. –General redundancy idea: Both Velo and UT have their own cooling plant Share 1 cooling plant in case of problems in the other. –What does this mean wrt chillers, piping and control? Crucial information still missing from UT and VELO for detailed design –Flow distribution and characteristics, ongoing –Safety system! -> Not much progress seen… The EDR in November should present a detailed P&ID and a draft Functional Analyses –Atlas IBL documents for reference: FA: https://edms.cern.ch/document/1233462https://edms.cern.ch/document/1233462 P&ID: https://edms.cern.ch/document/1233482https://edms.cern.ch/document/1233482 4 VeloUT

5. Redundancy approach How to make the system fully redundant? –Taking into account: Simplicity (both use and production) Rely on past experiences Cost Minimal interference between UT and Velo operation. –Basic idea: 2 identical plants with over capacity Use 1 plant for Velo and UT together in case 1 system is out of order (in case of maintenance or problems) –First a basic concept must be worked out How to use the chiller? –Dedicated or shared –Air-cooled / water cooled How to interlink the CO2 units –Mixing up content of 2 systems, influencing filling content –How to separate? Some 1 st thoughts given in the next slides 5

6. 6 Velo UT Option 1A: 1 chiller per plant, inter connection near detector A Shielding wall

7. Option 1B: 1 chiller for both plants (+spare), inter connection near detector 7 B B Shielding wall Velo UT

8. Option 2A: 1 chiller per plant, inter connection near the plant 8 A Shielding wall Velo UT

9. Option 2B: 1 chiller for both plants (+spare), inter connection near detector 9 B Shielding wall Velo UT CMS concept

10. Comparison CO 2 systems Advantages Option 1 –Small mix-up volume, no complex levelling procedure –Full system can be taken out of service –2 similar stand alone plants Option 2 –Simpler hardware in experimental cavern –Similar concept as CMS Disadvantages Option 1 –Active valves in experimental area Option 2 –More complex at plant level –Complex separation procedure Needs a de-mixing program 10

11. Comparison primary cooling Advantages Option A –Simple concept, direct connection to CO2 plant –Can operate independent from other system Option B –A chiller unit can be taken out of service when both CO2 plants are running –1 chiller can be air-cooled and the other water cooled to minimize chiller complexity –Constant load, easier to design and operate. Disadvantages Option A –Chiller can only be serviced when complete plant is off –Each chiller needs a back-up condenser (water/ air) –Runs most of the time in part load (more complex design) Option B –More complex piping 11

12. Summary UT status: –Requirements in a good shape, need formalization –Evaporator performance unknown, but will be rather straight forward. Velo status: –Complex micro channel behavior must be understood 1 st, not as straight forward as UT (new territory). –Safety system concept missing –Requirements must be finalized and formalized. Cooling system status –Conceptual thinking of redundant concept is starting. –Lots of work to be done for EDR in November 12