Flow Couplers for Liquid Metal Fast Breeder Reactors

Early on, the designers of liquid metal fast breeder reactors recognized that electromagnetic pumps were well suited to operation in that difficult environment. The high efficiency Flow Coupler offers the potential for a passive primary pumping system without reactor penetrations and without moving components.

In the Flow Coupler, fluid energy from the secondary mechanical pump is transferred electro-magnetically to drive the primary fluid. The primary and secondary liquid metal flows are arranged in multiple adjacent ducts in a common steady magnetic field. A direct current generated by the moving fluid in the secondary duct circulates through the primary duct and interacts with the field to cause a pressure rise that in turn drives the primary flow. The Flow Coupler many be conveniently arranged to be coaxial with each primary heat exchanger.

“The High Efficiency Flow Coupler: a New Approach to Pumping Sodium in Liquid Metal Reactors.” 5 th Beer-Sheva Seminar on MHD Flows and Turbulence. Beer-Sheva, Israel. March, 1987

“Demonstration of Flow Couplers for the LMFBR.” Single and Multi-Phase Flows in an Electromagnetic Field. Energy, Metallurgical, and Solar Applications. Progress in Astronautics and Aeronautics. Volume 100. 1985.