Toward Analysis of Corium Hydraulics in Liquid Sodium

During a hypothetical severe accident in a sodium-cooled fast reactor, core melt-down is expected to occur. As a result, molten corium would fall through sodium as a jet. The dispersion of the fissile material within the molten jet is important to avoid re-criticality. This occurs in several stages with different sequence of complex controlling physical phenomena. The present work is in the direction of understanding the initial jet behavior influenced primarily by flow instabilities. An in-house force balanced two-phase flow solver, namely THYC-MP has been used to study the behavior of two-dimensional jets of corium and simulant material namely wood’s metal within liquid sodium. The expected physics and jet breakup behavior is studied and described.