The first experiments have been run using electrically heated, simulated fuel elements in an inert gas (argon) loop. The fuel elements have a chopped cosine power input and have a Pb/Sn alloy cladding. Single elements were used in the first two experiments with a step power pulse of about 1 kW/ft which was sufficient to melt the center of the clad within 8 to 10 sec. As the molten cladding entered the blanket (unheated) region, it froze within about 1 inch. The apparatus for the stainless steel pouring experiment is progressing. Additional models for freezing of molten cladding in colder regions are being analyzed and tested against the single tube pouring tests previously reported. Analytical routines are under development.

Progress is summarized in the areas of SOMIX code development, simulated fuel element source term studies, aerosol leakage tests and calculations, fuel and fission product release from burning sodium, aerosol source term from vaporized fuel properties of high temperature fuel mixtures, and aerosol source from MCFI.