Performance Prediction of Nb3Sn CICC’s

Mark D. Bird (NHMFL-FSU), DMR 0603042

Research: Cable-in-Conduit Conductors using Nb3Sn are critical to the development of the NHMFL’s Series-Connected Hybrid as well as ITER. A unique facility has been built at the NHMFL to test CICC’s at high field, high current and high strain. 6 CICC’s have now been tested: current-sharing temperature data is shown in Fig. 1. The Florida Electro-Mechanical Cable Model has been developed and benchmarked with good agreement against 40 CICC’s tested worldwide as shown in Fig. 2. The NHMFL has demonstrated that both thermal and electromagnetic bending play important roles in the performance of Nb3Sn CICC’s. This information is facilitating the construction of CICC magnets for the NHMFL, the Helmholtz Center Berlin, SNS, and ITER.

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Applied strain (%)

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Fig. 1. Current-sharing temperature vs strain for CICC’s tested at the NHMFL

Fig. 2. Measured critical current of CICC’s tested worldwide correlated with FEMCAM

Performance Prediction of Nb3Sn CICC’s

Mark D. Bird (NHMFL-FSU), DMR 0603042

Broader Impacts: The Series-Connected hybrid projects at the NHMFL are educating students at all levels. 1) Julia Luongo, an undergraduate at Swarthmore, performed supercritical helium cooling calculations for the CICC coil.

2) Ting Xu, a postdoc in MS&T, is playing a leading role in designing and testing the 20 kA joints for the SCH outsert.

3) Electrical Engineering graduate students Mingzhou Li and Jenna Samra at Penn State tested the field-regulation system for the Series-Connected hybrid

4) Approximately 4600 people visited the NHMFL on February 23, 2008 for the Annual NHMFL Open House. Visitors included many children from rural North Florida. The winding equipment for the Series-Connected hybrid was on display as well as computer-aided-design stations, real magnet parts and models of various magnets still being designed and built.

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