Some very preliminary thermal estimates for the DUNE Near Detector - - PowerPoint PPT Presentation

Some very preliminary thermal estimates for the DUNE Near Detector Superconducting Solenoid and order

• f magnitude comparisons to Mu2e

Terry Tope - DUNE Near Detector Meeting 2-22-19

Dimensions for thermal radiation and mass calcs

• Thomas Strauss provided some coil dimensions

– Assumptions

• Coldmass 35 cm x 35 cm cross-section (coil + strongback)
• Each coldmass in its own cryostat
• Cold supports likely required between cryostats (not modeled)

– May lead to a common insulating vacuum

• 80 K thermal shield surrounding each coldmass with 10 cm gap

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Sketch of coldmass

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Thermal radiation calculations

• Surface area of coldmass and thermal shield calculated
• Multiplied by MLI mfg heat flux data with 1.5x safety factor
• 77 K – 4 K assumed 10 layers at 0.03 W/m^2
• 300 K – 77 K assumed 40 layers at 0.825 W/m^2

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Thermal radiation calculations

• Coldmass (all 5 coils)

– Surface area 179 m^2 – 77 K to 4.7 K thermal radiation 5.4 W

• Support conduction to room temp likely to be several times this….
• Also will have HTS power lead heat load 15 W at 10 kA

– 42.3 tonne (assumed to be aluminum)

• Thermal shield (all 5 coils)

– Surface area 281 m^2 – 300 K to 77 K thermal radiation 232 W

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Comparison to Mu2e Solenoids

• Mu2e solenoids look very different but interesting to compare

mass and thermal aspects

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