Low Thermal Conductance Torque Tube

"The U.S. Navy and private industry are investing heavily inseveral ship electric drive systems. Composite drive shafts withoptimized high torque end fittings hold promise for significantweight reduction. In the HTS ac synchronous motor a compositetorque tube system is necessary for magnet support to minimizeheat leak to the rotating HTS coilsFoster-Miller, teamed with American Superconductor (ASC) andAlliant TechSystems (ATK) has successfully completed a Phase Istudy and design development for a low thermal conductance torquetube system designed to provide less than 20W of heat. Thestraightforward design is easy to install, eliminates the needfor magnet support straps and minimizes thermal expansionmismatch issues. It is a direct substitution into the AmericanSuperconductor HTS ac synchronous ship drive motor but is equallyapplicable to their commercial systems.The design and fabrication provide the dual advantages ofsuperior structural and thermal performance along withsubstantially reduced manufacturing and installation costs. Withfull-scale demonstration planned for Phase II and the strongfabrication and system integration team, which includes thesupport of Ingalls Shipbuilding, Foster-Miller is well positionedto support development of the HTS ac synchronous ship electricdrive system for application to DD21. (P-01436)BENEFITS: The proposed program will develop an advanced composite ship drive shaft system. This will support the HT