General information
Organisation
The French Alternative Energies and Atomic Energy Commission (CEA) is a key player in research, development and innovation in four main areas :
• defence and security,
• nuclear energy (fission and fusion),
• technological research for industry,
• fundamental research in the physical sciences and life sciences.
Drawing on its widely acknowledged expertise, and thanks to its 16000 technicians, engineers, researchers and staff, the CEA actively participates in collaborative projects with a large number of academic and industrial partners.
The CEA is established in ten centers spread throughout France
Reference
SL-DRF-25-0684
Direction
DRF
Thesis topic details
Category
Engineering science
Thesis topics
Analysis and experimental study of capillary structures to mitigate the influence of magnetogravitational forces on liquid helium cooling for future HTS superconducting magnets
Contract
Thèse
Job description
As physics requires increasingly higher magnetic fields, CEA is called upon to develop and produce superconducting magnets capable of generating magnetic field of more than 30 T. The windings of these electromagnets are made from superconducting materials whose electrical resistance is extremely low at cryogenic temperatures (a few Kelvins). This enables them to carry high currents (>10 kA) while dissipating a minimum of heat by Joule effect. Cooling at these low temperatures is achieved using liquid helium. But helium is diamagnetic. Magnetic fields will therefore induce volumetric forces that add to or oppose gravity within the helium. These magneto-gravity forces disrupt the convective phenomena required to cool the superconducting magnet. This can lead to a rise in their temperature and a loss of their superconducting state, which is essential for their proper operation. In order to circumvent this phenomenon, a new cooling system never used in cryomagnetism will be studied. This cooling system will be developed using heat pipes whose operation is based on capillary forces that are theoretically independent of the magneto-gravity forces induced by strong magnetic fields. These capillary structures can take several forms (microchannels, foam, mesh, etc.). In the framework of the thesis these different structures will be studied theoretically and then experimentally, both with and without magnetic forces, in order to determine the most suitable structures for the future superconducting magnets.
University / doctoral school
PHENIICS (PHENIICS)
Paris-Saclay
Thesis topic location
Site
Saclay
Requester
Position start date
01/10/2025
Person to be contacted by the applicant
BAGNIS Simon
simon.bagnis@cea.fr
CEA
DRF/IRFU/DACM/LCSE
CEA Saclay
DRF/Irfu/DACM
Bâtiment 123
91191 Gif-sur-Yvette
0169083156
Tutor / Responsible thesis director
BAUDOUY Bertrand
bertrand.baudouy@cea.fr
CEA
DRF/IRFU/DACM/LCSE
CEA Saclay
DRF/Irfu/DACM
Bâtiment 123
91191 Gif-sur-Yvette
0169084207
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