Multidimensional multiphysics simulations of the supercritical water-cooled fuel rod behaviors based on a new fuel performance code developed on the MOOSE platform

Abstract

Traditional nuclear fuel performance codes usually employ the operator split methods for multiphysics coupling and the quasi-two-dimensional approach (1.5D approach) for geometry modelling. However, the multiphysics behavior of the fuel element is often tightly coupled, and there exist some kinds of non-axisymmetric fuel elements in reactors. In this paper, a new fuel performance code named NECP-CALF has been developed based on the Multiphysics Object-Oriented Simulation Environment (MOOSE). It solves the multiphysics coupled equations using the JFNK method. A new geometrical approach called mixed dimensional approach is implemented in the new code, which allows users to model fuel elements with more flexibility. A UO2-Zr fuel rod is simulated and the results are compared with BISON and CAMPUS to establish the proof-of-concept of this code. Then a small-scale UO2-Zr fuel rod with azimuthally asymmetric cladding temperature is designed and simulated with the mixed dimensional approach to verify the accuracy and demonstrate the performance. Finally, the code is applied to the fuel performance simulation of a supercritical water-cooled fuel rod with flow blockage, and the results show the impact of the flow blockage on the fuel rod performance.