. 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

. Si upgrade workshop, 9 June 2003 - Hubert van Hecke

services

. Si upgrade workshop, 9 June 2003 - Hubert van Hecke

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