Final Cooling Solenoid - Progress Meeting

Friday 24 Apr 2026, 14:00 → 16:00 Europe/Zurich

376/1-020 (CERN)

● Tooling assembly for cryogenic tests

• The finalisation is planned for the beginning or middle of next week, with the help of a subcontractor.
• Modifications for the tests in Grenoble will need to be made.

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● Updates on the experimental activities in 163

Hardware

• The new 77 K measurement setup is operational and currently in use.
• Current injection leads needed to be upgraded, now double‑soldered REBCO tape.
• The cryostat lid is in final design and will be fully 3D‑printed, with the aim of reducing LN₂ consumption and contamination.
• First coil measurements (MHW‑050) completed; voltage and Hall probe data are available for the HTS benchmarking group.
  • The agreed TOML configuration file is not yet available but is expected shortly.
• Preparation of the 4.2 K setup (B163) is ongoing.

Software

• The new DAQ software is functional for basic acquisition.
• Core features (device management, live plotting, data storage) are implemented.
• Current priorities: bug fixing, performance optimization, and power supply (Lambda) control.

Analysis & Microscopy

• Microscopy studies (EN‑MME) are ongoing to investigate winding alignment.
• Small coil samples have been analyzed; a coil will be impregnated and sectioned for further study.
• Comparison of tape geometry between coil center and outer regions is planned.

B163 Measurements

• 2 mm SuperMag tape tested at 4.2K:
  • Parallel-field measurements completed.
  • Perpendicular-field measurements planned.

Open Points

• Clarify whether the magnet (of test station 2) will remain inside the cryostat for the 4.2 K tests.

Vertical Scanning Interferometry

• Study for master thesis of Dairis
• 25 um curvature on flat tape

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● Update on the NICQS loads input in Ansys mechanical

• NICQS load inputs implementation into ANSYS is running
• Simulations with 1 kA current and a 20 T background field indicate a hub stress of approximately 3 GPa, exceeding acceptable limits
  
  • Reduce current density by adapting the coil design
  • Design a special coil configuration, including co-winding HTS tape with Hastelloy tape
  • Decrease the time constant of the coil
  • Operate the coil at lower current
  • Apply slower ramping of the external magnetic field

• Update mechanical simulations accordingly
• Simulation including cooldown

14:00 → 14:20 Tooling assembly for cryogenic tests

Speaker: Frantisek Sanda (CERN)

• The finalisation is planned for the beginning or middle of next week, with the help of a subcontractor.
• Modifications for the tests in Grenoble will need to be made.

14:20 → 14:40 Updates on the experimental activities in 163

Speakers: Alessio Simoni (Politecnico di Milano (IT)), Konstantin Weindel

FCS_23_04_towards4K_Final.pdf

FCS_23_04_towards4K_Final.pptx

Hardware

• The new 77 K measurement setup is operational and currently in use.
• Current injection leads needed to be upgraded, now double‑soldered REBCO tape.
• The cryostat lid is in final design and will be fully 3D‑printed, with the aim of reducing LN₂ consumption and contamination.
• First coil measurements (MHW‑050) completed; voltage and Hall probe data are available for the HTS benchmarking group.
  • The agreed TOML configuration file is not yet available but is expected shortly.
• Preparation of the 4.2 K setup (B163) is ongoing.

Software

• The new DAQ software is functional for basic acquisition.
• Core features (device management, live plotting, data storage) are implemented.
• Current priorities: bug fixing, performance optimization, and power supply (Lambda) control.

Analysis & Microscopy

• Microscopy studies (EN‑MME) are ongoing to investigate winding alignment.
• Small coil samples have been analyzed; a coil will be impregnated and sectioned for further study.
• Comparison of tape geometry between coil center and outer regions is planned.

B163 Measurements

• 2 mm SuperMag tape tested at 4.2K:
  • Parallel-field measurements completed.
  • Perpendicular-field measurements planned.

Open Points

• Clarify whether the magnet (of test station 2) will remain inside the cryostat for the 4.2 K tests.

Vertical Scanning Interferometry

• Study for master thesis of Dairis
• 25 um curvature on flat tape

14:40 → 15:00 Update on the NICQS loads input in Ansys mechanical

Speakers: Audrey Jade Ventura (EPFL - Ecole Polytechnique Federale Lausanne (CH)), Dr Tim Mulder (CERN)

• NICQS load inputs implementation into ANSYS is running
• Simulations with 1 kA current and a 20 T background field indicate a hub stress of approximately 3 GPa, exceeding acceptable limits
  
  • Reduce current density by adapting the coil design
  • Design a special coil configuration, including co-winding HTS tape with Hastelloy tape
  • Decrease the time constant of the coil
  • Operate the coil at lower current
  • Apply slower ramping of the external magnetic field

• Update mechanical simulations accordingly
• Simulation including cooldown

15:00 → 15:20 Optical profilometry of REBCO HTS strips in flat condition and at different winding radii in order to study the anticlastic effect due to winding

https://edms.cern.ch/document/3454347/1

Speaker: Jorge Guardia Valenzuela (CERN)