Download - Si Upgrade - Mechanics
. Si upgrade workshop, 9 June 2003 - Hubert van Hecke
Si Upgrade - Mechanics
• Review of Hytec study• Mounting scheme• Services
. Si upgrade workshop, 9 June 2003 - Hubert van Hecke
Hytec - material selectionMaterial for the support structure was selected on the basis of:
• High radiation length• Low density• High stiffness• Availability
Materials considered: Cons:
Availability, thermal expansion
Strength, thermal expansion, density, RL
• GFRP• Beryllium• Carbon-Carbon• Aluminum
Usually used for thermal apps.
. Si upgrade workshop, 9 June 2003 - Hubert van Hecke
material - cont’dGFRP - graphite fiber - epoxy composite: which fiber? Choose one based on cost, availability. M55J
. Si upgrade workshop, 9 June 2003 - Hubert van Hecke
strength analysisDifferent structures were tried….
… and analyzed for strength.Dumbbell shapes have low bending strength. Choose single-barrel shape.
. Si upgrade workshop, 9 June 2003 - Hubert van Hecke
build in sectionsAtlas Si detector
3 sections, bolted together
Endcap frame
. Si upgrade workshop, 9 June 2003 - Hubert van Hecke
coolingBased on the experiences with the Alice and Atlas cooling designs
• Negative pressure system• Water-methanol• CFC evaporative• CFC single-phase
And the lower total load (~2.2kW), and the lower power density (0.1-0.7 W/cm ) choose single-phase CFC
Run C6F14 or C5F12 at modest overpressure
2
. Si upgrade workshop, 9 June 2003 - Hubert van Hecke
cooling - cont’dEndcaps are cooledby tubes embeddedin the support sandwich.
Barrels are cooledwith carbon-Carbonthermal plane with‘Omega’ structure.
. Si upgrade workshop, 9 June 2003 - Hubert van Hecke
mounting scheme
TPC/HBD mountsfrom the top CM yoke.
The Silicon detectorcomes in from the bottom, much like the MVD does now.
Translate or clamshell?
. Si upgrade workshop, 9 June 2003 - Hubert van Hecke
side view - services
Power, cooling and signal services are brought in at both ends,using the entire perimeter.
. Si upgrade workshop, 9 June 2003 - Hubert van Hecke
services - powerPower: at 0.1W/cm for 1.8V technology
1 10.5 32 18 2 14.1 60 33 3 18.0 100 56 4 18.0 100 56
Total: 163A
If the voltage drop over 100’ is 1%, then this can be delivered via copper cable if the area is 28cm .Total for barrel + 2 endcaps: 190 cm of copper.
Disk r power(W) Current(A)
2
2
2
. Si upgrade workshop, 9 June 2003 - Hubert van Hecke
services - cooling
Count tubes on variousdrawings.
1/2 of one endcap
128 tubes for 2 endcaps, bundle 9/cm 14 cm total
Assume a similar area for the barrel
[ air cooling -> more area ]
2
2
. Si upgrade workshop, 9 June 2003 - Hubert van Hecke
services - fibers
Assume 1 fiber per ladder for the barrel,2 per ladder for the endcaps:
Barrel 86 cables = 16.9 cmEndcaps 64/end = 12.5 cm
Total for fibers: 42 cm
2
2
2
. Si upgrade workshop, 9 June 2003 - Hubert van Hecke
services - how much space
total area dz per end
From ‘first principles’ 352 cm 1.4cmCurrent MVD: ~50% of perimeter 940 cm 2.5cmRule-of-thumb from Veljko Radeka: 12% of Silicon area (Atlas) 1444 cm 5.7cm
Assume that services (power, air, liquid coolant, copper and fiber are brought in on both ends, usingthe entire perimeter at r=20cm.
2
2
2
. Si upgrade workshop, 9 June 2003 - Hubert van Hecke
to be studied
• Power distribution - local voltage conversion,mass issues• Cooling - can some be done with air?• Keep an eye on integration
For the next round, technology choices need to be pinned down
. Si upgrade workshop, 9 June 2003 - Hubert van Hecke
future
Our progress-to-manpower ratio compares favorably with industry standard.
Our progress-to-fundingratio compares favorably with
industry standards