Laboratoire National des Champs Magnétiques Pulsés CNRS – INSA

Evolution of standard DC resistive magnets
Based on the expertise that the LNCMI-G has acquired over the recent years with the polyhelix
technology, on recent advances in commercial copper alloys and radial cooling techniques, and backed
by extensive finite element modelling, it is extrapolated that DC resistive fields up to 39 T should be
possible, within a time span of 5 years (see figure below). The R&D to realize this potential will be
one of the priorities of the LNCMI-G for the coming years. Provided that the necessary financial
means can be found, this will bring the LNCMI back to the leading position in high magnetic field
technology.
The improved coil efficiency resulting from the above developments will also allow to generate
somewhat more modest fields (28+ Tesla) with only 12 MW electrical power consumption. This will
allow to operate two such magnets simultaneously, greatly increasing the LNCMI-G capacity and will
allow to do high field experiments at reduced electricity consumption. In view of the long term
sustainability of a high field facility, this latter aspect is becoming more and more important.
Another route to increasing the field strength available for experiments at constant electrical power
consumption and with the available conductors would be to reduce the bore size e.g. to 25 mm. This
will of course complicate cryogenics and other aspects of the experiments to be performed in such a
magnet. By implementing the bore size reduction by means of a magnet insert that operates at lower
temperature (e.g. cooled by liquid nitrogen), an even more significant gain in field strength, can be
obtained. First estimates suggest fields in excess of 42 T for such a configuration, which will be
studied and modelled in greater detail in the future.
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Réalisés
Avenir
1980 1990 2000 2010 2020
Evolution, realized and expected, of the maximum static magnetic field available at LNCMI-G
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