The reactor dynamics code DYN3D

Abstract

The article provides an overview on the code DYN3D which is a three-dimensional core model for steady-state, dynamic and depletion calculations in reactor cores with quadratic or hexagonal fuel assembly geometry being developed by the Helmholtz-Zentrum Dresden-Rossendorf for more than 20 years. The current paper gives an overview on the basic DYN3D models and the available code couplings. The verification and validation status is shortly outlined. The paper concludes with the current developments of the DYN3D code. For more detailed information the reader is referred to the publications cited in the corresponding chapters.

On the numerical modelling of frozen walls in a molten salt fast reactor

“…To simulate the neutronics of the MSFR with the nodal diffusion code, DYN3D-MG (Kliem et al, 2016;Rohde et al, 2016), neutronics calculations of the full-core MSFR were first performed using version 2.1.29 of the Monte Carlo Transport code SERPENT (Leppänen et al, 2015) in order to determine the reactor criticality and to prepare the homogenized macroscopic cross-sections that are supplied to the MSFR model, which was then solved in the steady state solver of DYN3D-MG. The homogenized macroscopic cross-sections are discretized into 27 neutron energy groups based on the ANL distribution of energies (Leppänen, 2017).…”

“…The coupling procedure implemented here uses a C++ library called the Multiscale Universal Interface, MUI, (Tang et al, 2015). DYN3D-MG was operated in the steady neutronics "feedback mode" without the internal thermal hydraulics module known as FLOCAL (Kliem et al, 2016;Rohde et al, 2016). Therefore, we consider that DYN3D-MG is a loosely coupled neutronics "inner iteration loop", which is external to the time step iteration loop of Code Saturne.…”