IAEA GT-MHR Benchmark Calculations using the HELIOS/MASTER Code Package

In this paper, the performance of the HELIOS/MASTER code package has been evaluated through the IAEA GT-MHR (Gas Turbine-Modular Helium Reactor) benchmark calculations with plutonium fuel. The proposed benchmark problems include five different cell models, two block models and six different core models. The computational results of the HELIOS and MASTER codes were compared with those of the MCNP code and other groups. The RPT method was used to remove a double heterogeneity in a fuel compact. The multiplication factors for the cell, block and core calculations agree well with those of the MCNP calculations. The multiplication factors and the radial and axial power distributions for the core calculations are very consistent with those of MCNP. From results above, it can be concluded that the HELIOS/MASTER 2-step procedure is available for the prismatic VHTR physics analysis. (authors)