MCNP6 calculation of neutron flux map in the HTTR during normal operation

Ho, H. Q.; Ishitsuka, Etsuo; Iigaki, Kazuhiko

Recent Contributions to Physics, 82(3), p.16 - 20, 2022/09

https://doi.org/10.26577/RCPh.2022.v82.i3.03

Computation speeds and memory requirements of mesh-type ICRP reference computational phantoms in Geant4, MCNP6, and PHITS

Yeom, Y. S.*; Han, M. C.*; Choi, C.*; Han, H.*; Shin, B.*; Furuta, Takuya; Kim, C. H.*

Health Physics, 116(5), p.664 - 676, 2019/05

https://doi.org/10.1097/HP.0000000000000999

Recently, Task Group 103 of the ICRP developed the mesh-type reference computational phantoms (MCRPs), which are planned for use in future ICRP dose coefficient calculation. Performance of major Monte Carlo particle transport codes (Geant4, MCNP6, and PHITS) were tested with MCRP. External and internal exposure of various particles and energies were calculated and the computational times and required memories were compared. Additionally calculation for voxel-mesh phantom was also conducted so that the influence of different mesh-representation in each code was studied. Memory usage of MRCP was as large as 10 GB with Geant4 and MCNP6 while it is much less with PHITS (1.2 GB). In addition, the computational time required for MRCP tends to increase compared to voxel-mesh phantoms with Geant4 and MCNP6 while it is equal or tends to decrease with PHITS.

Multi-threading performance of Geant4, MCNP6, and PHITS Monte Carlo codes for tetrahedral-mesh geometry

Han, M. C.*; Yeom, Y. S.*; Lee, H. S.*; Shin, B.*; Kim, C. H.*; Furuta, Takuya

Physics in Medicine & Biology, 63(9), p.09NT02_1 - 09NT02_9, 2018/05

https://doi.org/10.1088/1361-6560/aabd20

The multi-threading computation performances of the Geant4, MCNP6, and PHITS codes were evaluated using three tetrahedral-mesh phantoms with different complexity. Photon and neutron transport simulations were conducted and the initialization time, calculation time, and memory usage were measured as a function of the number of threads N used in the simulation. The initialization time significantly increases with the complexity of the phantom, but not much with the number of the threads. For the calculation time, Geant4 showed good parallelization efficiency with multi-thread computation (30 times speed-up factor for N = 40) adopting the private tallies while saturation of the speed-up factor were observed in MCNP6 and PHITS (10 and a few times for N = 40) due to the time delay for the sharing tallies. On the other hand, Geant4 requires larger memory specification and the memory usage rapidly increases with the number of threads compared to MCNP6 or PHITS. It is notable that when compared to the other codes, the memory usage of PHITS is much smaller, regardless of both the complexity of the phantom and the number of the threads.

Benchmark of neutron production cross sections with Monte Carlo codes

Tsai, P.-E.; Lai, B.-L.*; Heilbronn, L. H.*; Sheu, R.-J.*

Nuclear Instruments and Methods in Physics Research B, 416, p.16 - 29, 2018/02

https://doi.org/10.1016/j.nimb.2017.11.029

Fifteen thin target experiments were selected for this benchmark study of the neutron production cross sections. The studied cases include a mix combination of C, Ne Ar, Kr, and Xe ions bombarding Li, C, Al, Cu, and Pb target with projectile energies between 135 and 600 MeV/nucleon. The experimental data were compared to the model calculations performed by (1) PHITS version 2.73 with JQMD and GEM model, (2) PHITS version 2.82 with revised JQMD 2.0 and GEM model, (3) FLUKA version 2011.2c with RQMD 2.4 and FLUKA's own de-excitation model, and (4) MCNP6 version 1.0 with LAQGSM 03.03 and GEM2 model. This study provides useful information not only for code users but also for model developers, and it will lead to future improvements of the PHITS - JQMD model for heavy-ion induced reactions, which is important for accelerator facilities, heavy-ion radiotherapy, and space radiation.

Benchmark study on realized random packing model for coated fuel particles of HTTR using MCNP6

Ho, H. Q.; Morita, Keisuke*; Honda, Yuki; Fujimoto, Nozomu*; Takada, Shoji

Proceedings of 2017 International Congress on Advances in Nuclear Power Plants (ICAPP 2017) (CD-ROM), 8 Pages, 2017/04

Investigation of the impact of difference between open nuclear data processing codes on neutron transport calculations, 3; Difference of nuclear data processing method

Tada, Kenichi; Ikehara, Tadashi; Ono, Michitaka*; Tojo, Masayuki*

no journal, , 

JAEA develops a nuclear data processing code FRENDY. We can comparison and verification of conventional nuclear data processing code using FRENDY. In this presentation, we focus on the thermal scattering law data. We found some problems of NJOY to process the thermal scattering law data as follows, (1) The generation of input file is complex and we found some inputting error in the official ACE library, (2) The maximum energy of ACE file is not identical to the inputted maximum energy, (3) If user uses iwt=2 option in ACER module, MCNP6.1 cannot treat this generated ACE file appropriately and the calculation will not completed This presentation explains the overview of these problems.