DOI QR코드

DOI QR Code

추락낙하 사고 시 지면과 충돌하는 고준위폐기물 처분용기의 비선형구조해석

Nonlinear Structural Analysis of the Spent Nuclear Fuel Disposal Canister Subjected to an Accidental Drop and Ground Impact Event

  • 권영주 (홍익대학교 기계정보공학과)
  • Kwon, Young-Joo (Department of Mechanical & Design Engineering, Hongik Univ.)
  • 투고 : 2018.08.23
  • 심사 : 2019.02.08
  • 발행 : 2019.04.30

초록

원자력발전의 최대 걸림돌은 사용 후 핵연료인 고준위폐기물이다. 높은 방사능과 발생하는 열은 사용 후 핵연료의 안전한 처분을 어렵게 하고 있다. 현재 유일한 처리방법은 심지층 처분기술이다. 본 논문은 이와 같은 심지층 처분기술의 핵심기술 중의 하나인 처분용기의 구조안전성 설계문제를 다루고 있다. 특히 처분장에서 처분용기 처분 시 사고로 운송차량에서 추락낙하 하여 지면과 충돌하는 경우 처분용기에 가해지는 충격력에 의하여 처분용기에 발생하는 응력 및 변형에 대한 비선형구조해석을 수행하였다. 해석의 주된 내용은 심지층 처분장에서 운반차량으로 처분용기 운반 중 사고로 추락낙하 하여 지면과의 충돌 시에 처분용기에 가해지는 충격력을 기구동역학해석 상용 컴퓨터코드인 RecurDyn으로 구하고 이 충격력에 의하여 처분용기에 발생하는 응력 및 변형을 유한요소 정적 구조해석 상용 컴퓨터코드인 NISA를 이용하여 구한 것이다. 해석결과는 충돌 충격 시간 중 발생하여 처분용기에 가해지는 충격력에 의하여 처분용기, 특히 처분용기의 위 덮개 혹은 아래 덮개에 큰 응력과 대변형이 발생함을 보여주고 있다.

The biggest obstacle in the nuclear power generation is the high level radioactive waste such as the spent nuclear fuel. High level radioactivities and generated heat make the safe treatment of the spent nuclear fuel very difficult. Nowadays, the only treatment method is a deep geological disposal technology. This paper treats the structural safe design problem of the spent nuclear fuel disposal canister which is one of the core technologies of the deep geological disposal technology. Especially, this paper executed the nonlinear structural analysis for the stresses and deformations occurring in the canister due to the impulsive force applied to the spent nuclear fuel disposal canister in the case of an accidental drop and ground impact event from the transportation vehicle in the repository. The main content of the analysis is about that the impulsive force is obtained using the commercial rigid body dynamic analysis computer code, RecurDyn, and the stress and deformation caused by this impulsive force are obtained using the commercial finite element static structural analysis computer code, NISA. The analysis results show that large stresses and deformations may occur in the canister, especially in the rid or the bottom of the canister, due to the impulsive force occurring during the collision impact period.

키워드

참고문헌

  1. Aquaro, D., Forassasi, G. (1983) Impact Tests on Scale Models of a Shock Absorber for LWR Spent Fuel Transport Packaging, 7th International Conference on Structural Mechanics in Reactor Technology, Chicago, USA.
  2. Choi, W.S., Seo, K.S. (2010) A Simple Sizing Optimization Technique for an Impact Limiter Based on Dynamic Material Properties, Nucl. Eng. & Des., 240, pp.925-932. https://doi.org/10.1016/j.nucengdes.2009.12.008
  3. Dierch, R., Weiss, M., Dreier, G. (1994) Investigation of the Impact Behaviour of Wooden Impact Limiter, Nucl. Eng. & Des., 150, pp.341-348. https://doi.org/10.1016/0029-5493(94)90153-8
  4. IAEA(International Atomic Energy Agency) (1996) IAEA Safety Standards Series No.ST-1, Regulations for the Safe Transport of Radioactive Materials, Vienna, Austria.
  5. KINS(Korea Institute of Nuclear Safety) (2015) Regulatory Standards and Guides No.KINS/RSN12.00 for PWR.
  6. Kwon, Y.J. (2010) Finite Element Analysis of Transient Heat Transfer in and Around a Deep Geological Repository for a Spent Nuclear Fuel Disposal Canister and the Heat Generation of the Spent Nuclear Fuel, Nucl. Sci. & Eng., 164, pp.264-296. https://doi.org/10.13182/NSE09-11
  7. Kwon, Y.J. (2011) Structural Analysis of PWR (Pressurized Water Reactor) Canister for Applied Impact Force Occurring at the Moment of Falling Plumb Down Collision, J. Comput. Struct. Eng. Inst. Korea, 24(2), pp.211-222.
  8. Kwon, Y.J. (2013) Rigid Body Dynamic Analysis on the Spent Nuclear Fuel Disposal Canister under Accidental Drop and Impact to the Ground: Numerical Analysis, J. Comput. Struct. Eng. Inst. Korea, 26(5), pp.373-384. https://doi.org/10.7734/COSEIK.2013.26.5.373
  9. Kwon, Y.J. (2016) Impact Force Applied on the Spent Nuclear Fuel Disposal Canister that Accidentally Drops and Collides on to the Ground, Trans. Korean Soc. Mech. Eng. A, 40(5), pp.469-481. https://doi.org/10.3795/KSME-A.2016.40.5.469
  10. Kwon, Y.J. (2017) Comparative Study of Finite Element Analysis for Stresses Occurring in Various Models of the Spent Nuclear Fuel Disposal Canister due to the Accidental Drop and Impact on to the Ground, J. Comput. Struct. Eng. Inst. Korea, 30(5), pp.415-425. https://doi.org/10.7734/COSEIK.2017.30.5.415
  11. Kwon, Y.J., Kang, S.W., Choi, J.W., Kang, C.H. (2001) Structural Analysis for the Determination of Design Variables of Spent Nuclear Fuel Disposal Canister, KSME Int. J., 15(3), pp.327-338. https://doi.org/10.1007/BF03185216
  12. Lee, J.Y., Cho, D.K., Choi, H.J., Choi, J.W. (2007) Concept of a Korean Reference Disposal System for Spent Fuel, J. Nucl. Sci. & Technol., 44(12), pp.1565-1573. https://doi.org/10.1080/18811248.2007.9711407
  13. Lee, Y.S., Kim, Y.J., Choi, Y.J., Kim, W.T. (2005) A Study on the Dynamic Impact Response Analysis of Cask by Modal Superposition Method, J. Comput. Struct. Eng. Inst. Korea, 18(4), pp.373-383.
  14. Miller, G.K. (1993) Calculation of Impact Loads for High Energy Drops of Cylindrical Containers, Int. J. Impact Eng., 13(4), pp.511-526. https://doi.org/10.1016/0734-743X(93)90083-J
  15. MOST (2001) Regulations on Shipping and Transportation of the Radioactive Materials.
  16. NRC Regulatory Guide 7.6 (1978) Design Criteria for the Structural Analysis of Shipping Cask Containment Vessels, USNRC.
  17. NSSC (2014) Notice 2014-50: Regulations on Shipping and Transportation of the Radioactive Materials.
  18. Pugliese, G., Frano, R.L., Forasassi, G. (2010) Spent Fuel Transport Cask Thermal Evaluation under Normal and Accident Conditions, Nucl. Eng. & Des., 240, pp.1699-1706. https://doi.org/10.1016/j.nucengdes.2010.02.033
  19. Teper, W.W., Suave, R.G. (1989) Simplified Method for Predicting Impact Loads of Solid-walled Transportation Packagings for Radioactive Materials, J. Press. Vessel Technol., 111, pp.316-321. https://doi.org/10.1115/1.3265681
  20. Wang, B., Gea, H.C., Kwon, Y.J. (2014) Finite Element Analysis of Stresses and Deformations Occurring in the Spent Nuclear Fuel(SNF) Disposal Canister Deposited in a Deep Geological Repository, Nucl. Eng. & Des., 266, pp.166-179. https://doi.org/10.1016/j.nucengdes.2013.10.030
  21. Zhou, C.Y., Yu, T.X., Lee, R.S.W. (2008) Drop/Impact Tests and Analysis of Typical Portable Eletronic Devices, Int. J. Mech. Sci., 50, pp.905-917. https://doi.org/10.1016/j.ijmecsci.2007.09.012
  22. Zhou, W., Apted, M.J., Kessler, J.H. (2010) The Thermal-hydrological Impact on Increased Spent Fuel Storage Capacity in Yucca Mountain Repository, Nucl. Technol., 170, pp.336-352. https://doi.org/10.13182/NT10-A9487