A pseudo-material method for graphite with arbitrary porosities in Monte Carlo criticality calculations

ABSTRACT

The latest ENDF/B-VIII library adapted new porosity-dependent cross-section data of graphite. However, the porosity of the actual graphite does not necessarily correspond to the porosity given in the data. We have proposed a method to perform neutronic calculations at the desired porosity on the basis of the pseudo-material method. We have also compared the k_eff values calculated by the pseudo-material method with the experimental values for the VHTRC. In addition, we have investigated the temperature dependance of the calculation values obtained by this method. From these results, we have concluded that this method allows us to perform the neutronic calculations in which we can reflect detailed information on the porosity of graphite.

KEYWORDS:

• ENDF/b-viii
• graphite
• porosity-dependent cross-section data
• vhtrc
• pseudo-material method

Acknowledgments

The authors would like to express our sincere appreciation and gratitude to Dr. Y. Kitamura of Kyoto University and Mr. Y. Eguchi of JAEA for providing valuable data of the VHTRC. The authors are deeply thankful to Dr. K. Tada of JAEA for his technical support of the FRENDY code. The helpful comments on this study by Dr. M. Goto of JAEA have contributed substantially to this work. The authors also wish to thank Dr. J. Sumita of JAEA for his helpful comments of reactor graphite.

Disclosure statement

The authors have no conflicts of interest directly relevant to the content of this article.