Earticle

초록

영어

Background: To prevent small leakage accidents, a real-time and direct detection system for small leaks with a detection limit below that of existing systems, e.g. 0.5 gpm·hr-1, is required. In this study, a small-size beta detector, which can be installed inside the reactor containment (CT) building and detect small leaks directly, was suggested and its feasibility was evaluated using MCNPX simulation. Materials and Methods: A target nuclide was selected through analysis of radiation from radionuclides in the reactor coolant system (RCS) and the spectrum was obtained via a silicon detector simulated in MCNPX. A window was designed to reduce the background signal caused by other nuclides. The sensitivity of the detector was also estimated, and its shielding designed for installation inside the reactor CT. Results and Discussion: The beta and gamma spectrum of the silicon detector showed a negligible gamma signal but it also contained an undesired peak at 0.22 MeV due to other nuclides, not the 16N target nuclide. Window to remove the peak was derived as 0.4 mm for beryllium. The sensitivity of silicon beta detector with a beryllium window of 1.7 mm thickness was derived as 5.172 × 10-6 μCi·cc-1. In addition, the specification of the shielding was evaluated through simulations, and the results showed that the integrity of the silicon detector can be maintained with lead shielding of 3 cm (<15 kg). This is a very small amount compared to the specifications of the lead shielding (600 kg) required for installation of 16N gamma detector in inside reactor CT, it was determined that beta detector would have a distinct advantage in terms of miniaturization. Conclusion: The feasibility of the beta detector was evaluated for installation inside the reactor CT to detect small leaks below 0.5 gpm·hr-1. In future, the design will be optimized on specific data.

목차

ABSTRACT
Introduction
Materials and Methods
1. Determination of target nuclide
2. Beta/gamma spectrum from RCS radionuclides
3. Detector window design and sensitivity estimation
4. Shielding design
Results and Discussion
Conclusion
Acknowledgement
References

키워드

저자

• JaeYeong Jang [ Department of Nuclear Engineering, Hanyang University, Seoul, Korea ]
• Thomas Schaarschmidt [ Department of Nuclear Engineering, Hanyang University, Seoul, Korea ]
• Yong Kyun Kim [ Department of Nuclear Engineering, Hanyang University, Seoul, Korea ] Corresponding Author

참고문헌

발행기관

간행물

표지보기 관심저널 등록

• 간행물명

  방사선방어학회지 [Journal of Radiation Protection and Research]

• 간기

  계간

• pISSN

  2508-1888

• 수록기간

  1976~2026

• 등재여부

  KCI 등재,SCOPUS

• 십진분류

  KDC 559 DDC 629