IMPROVEMENT OF METHODS FOR MODELING THE MELTING OF FUEL ASSEMBLIES IN THE CONDITIONS OF AN EXPERIMENT ON IGR RECTOR

Experimental studies of the process of fuel destruction at the IGRY reactor make it possible to obtain data on the processes occurring in the fuel assemblies of various types of nuclear reactors during severe accidents. One of the stages of severe accidents is the melting of nuclear fuel. One of the stages of severe accidents is the melting of nuclear fuel. In this paper, we consider the complex application of physical models of the ANSYS FLUENT software module to achieve explicit dynamic melting of elements of a fuel assembly. Computational studies are carried out on a two-dimensional model of an experimental reactor device. The calculation models «volume of fluid» and «solidification melting» are used, which allow modeling the movements of the liquid fraction of the elements of the fuel assembly. To set the energy release, a user defined function (UDF) of the Fluent module is used.

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