MELCOR validation results

Recent comparisons of MELCOR predictions to three sets of experiments, the ABCOVE Aerosol Experiments, the HDR-V44 Steam Blowdown Experiments, and the Battelle-Frankfurt Gas Mixing Experiments are presentd. All three comparisons involve conditions that are of concern in an LWR containment during a severe accident. MELCOR results are compared to the experimental data and the predictions of at least one other state-of-the-art code for each test. In the ABCOVE comparisons, the MELCOR aerosol modeling is demonstrated. In comparisons to the HDR-V44 Steam Blowdown Experiments, MELCOR predictions of the response of the containment to the release of steam from the primary system are shown, and in the Battelle-Frankfurt comparisons, MELCOR predictions of the diffusion in a containment of an injected hydrogen-nitrogen gas are studied. These comparisons provide critical testing of the MELCOR control volume hydrodynamics package, the radionuclide package, and the flow path package