TET2MCNP: A Conversion Program to Implement Tetrahedral-mesh Models in MCNP

  • Han, Min Cheol (Department of Nuclear Engineering, Hanyang University) ;
  • Yeom, Yeon Soo (Department of Nuclear Engineering, Hanyang University) ;
  • Nguyen, Thang Tat (Department of Nuclear Engineering, Hanyang University) ;
  • Choi, Chansoo (Department of Nuclear Engineering, Hanyang University) ;
  • Lee, Hyun Su (Department of Nuclear Engineering, Hanyang University) ;
  • Kim, Chan Hyeong (Department of Nuclear Engineering, Hanyang University)
  • Received : 2016.08.22
  • Accepted : 2016.09.19
  • Published : 2016.12.31


Background: Tetrahedral-mesh geometries can be used in the MCNP code, but the MCNP code accepts only the geometry in the Abaqus input file format; hence, the existing tetrahedral-mesh models first need to be converted to the Abacus input file format to be used in the MCNP code. In the present study, we developed a simple but useful computer program, TET2MCNP, for converting TetGen-generated tetrahedral-mesh models to the Abacus input file format. Materials and Methods: TET2MCNP is written in C++ and contains two components: one for converting a TetGen output file to the Abacus input file and the other for the reverse conversion process. The TET2MCP program also produces an MCNP input file. Further, the program provides some MCNP-specific functions: the maximum number of elements (i.e., tetrahedrons) per part can be limited, and the material density of each element can be transferred to the MCNP input file. Results and Discussion: To test the developed program, two tetrahedral-mesh models were generated using TetGen and converted to the Abaqus input file format using TET2MCNP. Subsequently, the converted files were used in the MCNP code to calculate the object- and organ-averaged absorbed dose in the sphere and phantom, respectively. The results show that the converted models provide, within statistical uncertainties, identical dose values to those obtained using the PHITS code, which uses the original tetrahedral-mesh models produced by the TetGen program. The results show that the developed program can successfully convert TetGen tetrahedral-mesh models to Abacus input files. Conclusion: In the present study, we have developed a computer program, TET2MCNP, which can be used to convert TetGen-generated tetrahedral-mesh models to the Abaqus input file format for use in the MCNP code. We believe this program will be used by many MCNP users for implementing complex tetrahedral-mesh models, including computational human phantoms, in the MCNP code.


Supported by : Korea Foundation of Nuclear Safety (KOFONS), National Research Foundation of Korea


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