Post on 18-Jan-2018
description
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Energy Science Laboratories, Inc.Materials & Processing ESLI
Cooled Carbon Support Cooled Carbon Support BTeV Pixel DetectorsBTeV Pixel Detectors
Development Recommendations for 2001
T R Knowles3/7/01
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Energy Science Laboratories, Inc.Materials & Processing ESLI
FY00 Progress• Cooled carbon structure demo articles (full-scale)
– Lightweight – Rigid– Shingled surface– Porous chip mount – Al manifolds
• Issues– Resistance at tube wall is high
• Need to increase thermal conductance – Tubing cracked, leaked
• Need to increase toughness and assure leak-tightness
Fibrous surface for shingling with high contact conductance
Vertical high-k fibers with in-plane discrete fiber reinforcements
Tubes cemented in grooves
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Energy Science Laboratories, Inc.Materials & Processing ESLI
Increase Thermal Conductance• “Fintubing” Concept
– Improved fiber orientation – Issues: Precision? Manifolds?
• “Tubewall” Concept– Complete layer of tubing
• Tubing height < 1 mm – Issues: Precision, Rigidity?
Manifolds
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Energy Science Laboratories, Inc.Materials & Processing ESLI
Graphite Header Tubing• Sealed POCO graphite tube
– Tube machined from POCO – Pyrocarbon CVD seal coat
• Helium leak test – Light CVD seal reduced He
permeation to <5e-9 mL/s (most sensitive scale on leak detector)
– Expect heavier coat to seal even better (no helium leak signal)
• Good candidate for headers– May reinforce with carbon braid
to improve strength and toughness
POCO graphite rod
CVD POCO tube, (unreinforced – 8 ksi)
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Energy Science Laboratories, Inc.Materials & Processing ESLI
Tube Manifolding
• Carbon carbon construction– Tubular elements
• Large-gauge headers• Small-gauge lines
– Carbon joining• Carbonize bonding resin• Seal by pyrocarbon CVD
• Reinforcement options– Integral boss on graphite
header for larger tube/header interface
– Fabric reinforcements
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Energy Science Laboratories, Inc.Materials & Processing ESLI
FY01 Task 1Review Issues and Options
• THERMAL “fintube” and “tubewall” options– Fabricate small comparison articles
• STRUCTURAL fibercore; carbon fiber frame – Fabricate small comparison articles
• MANIFOLDING aluminum vs carbon – Fabricate carbon-carbon T-joint to test hermiticity
• TOUGHNESSreliable tube/manifold connection– Fabricate stress-relieved joints with velvet or fabric
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Energy Science Laboratories, Inc.Materials & Processing ESLI
FY01 Task 2Fabricate Prototypes
• Fabricate two (2) Cooled-Carbon Supports – Incorporate design features selected from Task 1
• Assure leak-tightness by monitoring throughout fabrication• Mount on aluminum frames; attach inlet and outlet lines
• Preliminary heat exchanger performance test at ESLI– Measure flow impedance– Measure heat exchanger performance
• Theater - Tcoolant when symmetrically heated @ 1 W/cm2
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Energy Science Laboratories, Inc.Materials & Processing ESLI
FY01 Task 3Superstructure Options
• Work together with FNAL engineering to draft design of support superstructure based on – Lightweight sandwich structures– Carbon tubing – Carbon truss superstructures
carbon rod space framebulkheads
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Energy Science Laboratories, Inc.Materials & Processing ESLI
Carbon Truss Structure Concept• Carbon sheet (100 µm) bulkheads• Carbon-fiber rods in tension• Carbon tubing & manifolds• Carbon fibercore thermal area
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Energy Science Laboratories, Inc.Materials & Processing ESLI
Cost/Schedule
Task Time (months) Cost ($k)
1. Design Selection 2 25
2. Prototype Fabrication 4 75
3. Superstructure 1 15