Graduate Students 2THEORETICAL STUDIES ON SOME ASPECTS OF MOLTEN-FUEL-COOLANT THERMAL INTERACTION

for the degree of Doctor of Philosophy. Rapid generation of high pressures and mechanical work may result when thermal energy is transferred from the hot molten nuclear fuel to the coolant in an LMFBR accident. Such energetic thermal interactions are facilitated by the large heat transfer area created when molten fuel is frag-mented in the coolant. Two aspects of the molten fuel-coolant interaction problem are investigated: (1) the effects of gas/vapor blanketing of the fuel on post-frag-mentation generation of pressure and mechanical work, and (2) the mechanism of the fragmentation of the molten fuel as it contacts the coolant. A model developed at Argonne National Laboratory to analyze fragmentation-induced energetic fuel-coolant inter