Thermodynamic properties and equations of state for fast reactor safety analysis: Part II: Properties of fast reactor materials Original Research Article

In this paper, thermodynamic properties of reactor-core materials are newly evaluated for an analytic equation-of-state (EOS) model with flexible thermodynamic functions. This model has been developed for a multiphase, multicomponent fluid-dynamics code for fast reactor safety analysis. The most up-to-date and reliable sources for uranium dioxide, mixed-oxide fuel, stainless steel, and sodium available at present are first compiled, with particular emphasis on including new thermodynamic data of type 316 stainless steel. This compilation is used to develop the EOS data up to the critical point using basic thermodynamic relationships. The EOS model for use in the accident analysis code is then completed by determining all the EOS parameters in the thermodynamic functions. The thermodynamic consistency and accuracy of the evaluated EOS data are also discussed by comparison with the available sources. The thermodynamic properties of sodium vapor are successively reproduced using a van der Waals type equation extended to include the dimerization process of sodium vapor.