Derivation of a Dryout Model in a Particle Debris Bed with the Drift-Flux Approach

A dryout model, based on the drift-flux approach to the separated two-phase countercurrent flow system with interfacial momentum transfer due to interphase friction, is derived in terms of a zero-dimensional and quasi-equilibrium form. The predictions of dryout heat flux in a large-particle debris bed within an overlying pool of saturated water and with complete blockage underneath are compared with various models and with the experimental results, which are available from the literature. The comparisons demonstrate the adequacy of the presented methodology.