Poschmann, MaxBernard W. N., FitzpatrickSimunovic, SrdjanPiro, Markus H. A. open-source equilibrium Thermochemistry library Thermochimica has previously been employed to study uranium dioxide nuclear fuel for light-water reactor (LWR) applications. Recently, significant improvements to the efficiency and range of applications of Thermochimica have been made. We will discuss these advances and demonstrate applications of Thermochimica for LWRs and next-generation nuclear technologies, such as Molten Salt Reactors (MSRs). Calculations on popular molten salt fuel materials, such as FliNaK, FliBe, and fission product containing salts, have been enabled through the implementation of the quadruplet approximation to the modified quasichemical model in Thermochimica, which takes into account first- and second-nearest-neighbor short-range ordering contributions to the Gibbs energies of liquid solution phases. Coupling of Thermochimica to various other software packages, such as the Multi-physics Object-Oriented Simulation Environment (MOOSE) app Bison and Oak Ridge Isotope GENeration (ORIGEN), for nuclear fuel applications will also be demonstrated. Future work will include further software coupling, such as with Coolant-Boiling in Rod Arrays–Two Fluids (CTF) and the Virtual Environment for Reactor Applications (VERA).
