Development of Two Types of Cryogen Free Superconducting Magnets (5T-ϕ300min and 10T-ϕ100mm)
Part of the
Advances in Cryogenic Engineering
book series (ACRE, volume 43)
An Ic-B-T characteristic (critical current vs. magnetic field at various temperatures) for multifilamentary NbTi superconducting (SC) wire has been measured by using a conduction cooled critical current measurement apparatus up to 300A and up to 5T, in the temperature range from 5K to 7.5K.
Two types of cryogen-free (C-F) SC magnets, a large bore type and a high field type, have been designed and fabricated based on these Ic-B-T characteristics for the multifilamentary NbTi SC wire. The large bore type and the high field type magnets generated 5T and 10T stable magnetic field at the center of the room temperature bore of 300mm and 100mm diameter, respectively.
The average heat generation while energizing is obtained based on the temperature dependence of the cryocooler’s cooling capacity. This average heat generation agrees well with the hysteresis loss of the whole magnet, calculated based on the hysteresis data for the multifilamentary NbTi short sample.
KeywordsRamp Rate Hysteresis Loss Bottom Flange Magnet Design Cryogenic Engineer
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