Review of potential models for UF[sub 6] dispersion

A survey of existing atmospheric dispersion models has been conducted to determine the most appropriate basis for the development of a model for predicting the consequences of an accidental UF[sub 6] release. The model is required for safety analysis studies and should therefore be computationally efficient. The release of UF[sub 6] involves a number of physical phenomena which make the situation more complicated than passive dispersion of a trace gas. The safety analysis must consider the density variations in the UF[sub 6] cloud, which can be heavier or lighter than the ambient air. The release also involves rapid chemical reactions and associated heat release, which must be modeled. Other Department of Energy storage facilities require a dense gas prediction capability, so the model must be sufficiently general for use with a variety of release scenarios. The special problems associated with UF[sub 6] make it unique, so there are very few models with existing capability for the problem. There are, however, a large number of dense gas dispersion models, some with relevant chemical reaction modeling, that could potentially form the basis of an advanced UF[sub 6] model. We have examined a large selection of possible candidates, and selected 5 models formore » detailed consideration.« less