Regenerative Cryogenic Helium Circulator

High Temperature Superconducting (HTS) cables offer major advantages over the conventional copper cables currently used to reduce the magnetic signatures of Navy ships. A degaussing system utilizing HTS cables would be smaller, lighter, and cost less to install than current systems. However, the cryogenic helium flow cooling system needed to keep the superconductor at its operating temperature can introduce additional cost and complexity. The cryogenic helium circulator is a key component in this cooling system, costing up to 20% of the total system cost. Creare is pursuing a development program to provide the Navy with the technology needed to transition an HTS Degaussing System into the next generation of warships. Here we propose a regenerative circulator that runs at a much lower speed than the centrifugal circulator used in the current system. The lower speed reduces the cost of the motor and bearings and enables a design for reduced heat leak. In Phase I, we will optimize the circulator design and operating point, and we will demonstrate the circulator performance. In Phase II, we will fabricate and test prototype circulators and demonstrate their performance in a representative degaussing system.