SUPERCONDUCTING WINDINGS AND SCREENING TE CHNIQUES FOR MHD THRUSTERS

Naval propulsion using MHD needs very high magnetic fields in large vo lumes to reach attractive efficiencies. On the other hand, the electro magnetic stealth leads to use multimodular thrusters to minimize the l eak fields, and to use internal and external shields, made with magnet ic or superconducting materials in case of damaged operation. Up to no w, the low temperature superconductors are the only materials able to fulfill these requirements. The encountered problems are of the same o rder than in fusion reactor systems, such as the ITER program now tind er study but a MHD thruster has to be set aboard a ship (submarine for example). The sum of the electromagnetical, cryogenical, hydrodynamic al and electrochemical problems will require long studies before the p ossibility to replace the classical line shafts by MHD thrusters can b e foreseen.