Application of Stiffness Confinement Method on Pin Resolved Variational Nodal Method and Its Implementation to C5G7-TD Benchmark Problem

This paper presents an implementation of the stiffness confinement method in the framework of the variational nodal method (VNM) to solve time-dependent pin resolved neutron transport equations. With frequency-transform, the time-dependent neutron transport equation is decoupled from the precursor equation and transformed into a transient eigenvalue problem (TEVP) which can be solved with the in-house VNM code VITAS-FE. The verification tests were performed using the C5G7-TD benchmark problems. The result agrees well with solutions of the MPACT. The study indicates that the VNM and SCM can be applied to solve the high-fidelity pin-resolved transient problem accurately.