Development of 160 m³/min Large Capacity Sodium-Immersed Self-Cooled Electromagnetic Pump

Abstract

A large capacity sodium-immersed self-cooled electromagnetic pump (LEMP) was developed for application to the main circulation pumps of FBR. This advanced LEMP is a submergible annular linear induction pump designed to be self-cooled by immersing into sodium and applying high temperature electrical insulation. Almost all the internal electrical losses were transferred to the surrounding sodium, which can be recovered as electricity by turbine generators. The LEMP having specifications of 160m3/min flow rate, 0.28 MPa head and more than 40% efficiency at the rating was designed, fabricated and tested in the sodium pump test facility. The test involves magnetic field measurement in the air and a variety of sodium tests during 2,550 h, which demonstrated good pump performance and flow controllability, and satisfied the design target. The boundary between flow stability and instability of the LEMP operation could be defined by peak position of the Q-H curve, which was specified by Rem×S (magnetic Reynolds' number times slip) of 1.4 to 1.5 at 335°C. Based on the test results, the applicability of the LEMP for the FBR was confirmed.