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 of 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 2

Sketch of coldmass 3

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 4

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 5

Comparison to Mu2e Solenoids • Mu2e solenoids look very different but interesting to compare mass and thermal aspects 6