The ABCOVE program: Preliminary results of tests AB5 and AB6

A program for aerosol behavior code validation and evaluation (ABCOVE) is in progress in the United States. The purpose of the ABCOVE program is to provide a basis for judging the adequacy of existing aerosol behavior computer codes to describe inherent aerosol behavior in containment buildings during postulated breeder reactor accidents. The program involves pretest calculations by code developers and users, large-scale confirmatory tests in the 850-m3 containment vessel of the Containment System Test Facility (CSTF), and blind post-test analyses and comparisons with experimental data. Two ABCOVE tests have been performed in the CSTF to date. In the first test, a single-species aerosol was used, with the aerosol generated by spraying sodium at a high rate into an air atmosphere. In the second test, the experimental conditions simulated an accident environment in which a fission product aerosol, NaI, was released in the presence of a sodium fire. Pretest computer code predictions were made by seven organizations using eight computer codes (HAA-3, HAA-4, HAARM-3, SOFIA, QUICK, QUICKM, MAEROS and CONTAIN). (orig.)