THE CONVERSION OF A ROOM-TEMPERATURE NAK LOOP TO A HIGH-TEMPERATURE MHD FACILITY FOR LI V BLANKET TESTING/

The Vanadium/Lithium system has been the recent focus of ANL's Blanket Technology Program, and for the last several years, ANL's Liquid Meta l Blanket activities have been carried out in direct support of the IT ER (International Thermonuclear Experimental Reactor) breeding blanket task area. A key feasibility issue for the ITER Vanadium/Lithium bree ding blanket is the development of insulator coatings. Design calculat ions, Hua and Gohar,(1) show that an electrically insulating layer is necessary to maintain an acceptably low magneto-hydrodynamic (MHD) pre ssure drop in the current ITER design. Consequently, the decision was made to. convert Argonne's Liquid Metal EXperiment (ALEX) from a 200 d egrees C NaK facility to a 350 degrees C lithium facility. The upgrade d facility was designed to produce MHD pressure drop data, test sectio n voltage distributions, and heat transfer data for mid-scale test sec tions and blanket mockups at Hartmann numbers (M) and interaction para meters (N) in the range of 10(3) to 10(5) in lithium at 350 degrees C. Following completion of the upgrade work, a short performance test wa s conducted, followed by two longer, multiple-hour, MHD tests, all at 230 degrees C. The modified ALEX facility performed up to expectations in the testing. MHD pressure drop and test section voltage distributi ons were collected at Hartmann numbers of 1000.