A study on transport and plugging of sodium aerosol in leak paths of concrete blocks
1
조회
0
다운로드
1
인용
0
참고문헌
키워드
초록
In the event of a severe accident in Sodium Cooled Fast Reactors (SFR), the sodium combustion aerosols along with fission product aerosols would migrate to the environment through leak paths of the Reactor Containment Building (RCB) concrete wall under positive pressure. Understanding the characteristics of sodium aerosol transport through concrete leak paths is important as it governs the environmental source term. In this context, experiments are conducted to study the influence of various parameters like pressure, initial mass concentration, leak path diameter, humidity etc., on the transport and deposition of sodium aerosols in straight leak paths of concrete. The leak paths in concrete specimens are prepared by casting and the diameter of the leak path is measured using thermography technique. Aerosol transport experiments are conducted to measure the transported and plugged aerosol mass in the leak paths and corresponding plugging times. The values of differential pressure, aerosol concentration and relative humidity taken for the study are in the ranges 10–15 kPa, 0.65–3.04 g/m3 and 30–90% respectively. These observations are numerically simulated using 1-Dimensional transport equation. The simulated values are compared with the experimental results and reasonable agreement among them is observed. From the safety assessment view of reactor, the approach presented here is conservative as it is with straight leak paths.
Abstract
In the event of a severe accident in Sodium Cooled Fast Reactors (SFR), the sodium combustion aerosols along with fission product aerosols would migrate to the environment through leak paths of the Reactor Containment Building (RCB) concrete wall under positive pressure. Understanding the characteristics of sodium aerosol transport through concrete leak paths is important as it governs the environmental source term. In this context, experiments are conducted to study the influence of various parameters like pressure, initial mass concentration, leak path diameter, humidity etc., on the transport and deposition of sodium aerosols in straight leak paths of concrete. The leak paths in concrete specimens are prepared by casting and the diameter of the leak path is measured using thermography technique. Aerosol transport experiments are conducted to measure the transported and plugged aerosol mass in the leak paths and corresponding plugging times. The values of differential pressure, aerosol concentration and relative humidity taken for the study are in the ranges 10–15 kPa, 0.65–3.04 g/m3 and 30–90% respectively. These observations are numerically simulated using 1-Dimensional transport equation. The simulated values are compared with the experimental results and reasonable agreement among them is observed. From the safety assessment view of reactor, the approach presented here is conservative as it is with straight leak paths.
참고문헌 (35)
- L. R. Bishnoi, "Prediction of air leakage and aerosol transport through concrete cracks with a fractal based crack morphology model", Nucl. Eng. Des, 265, pp.393~401 (2013)
- D. Mitrakos, "A simple mechanistic model for particle penetration and plugging in tubes and cracks", Nucl. Eng. Des, 238, pp.3370~3378 (2008)
- PFBR Preliminary safety analysis report, PFBR-PSAR. Chapter 15-Engineered Safety Features to Mitigate Accidents, , ~ (2004)
- F. Parozzi, "Investigation on aerosol transport in containment cracks", International Conference on Nuclear Energy for New Europe (2011)
- T. Gelain, "Research works on contamination transfers through cracked concrete walls", Nucl. Eng. Des, 238, pp.1159~1165 (2008)
- Aerosol Leakage Tests, Status of Safety Technology for Radiological Consequences of Postulated Accidents in Liquid Metal Fast Breeder Reactors, "C.T. Nelson", Energy Resources and Development Administration, ~, pp.ERDA-56 (1975)
- S. L. Sutter, "Depleted uranium dioxide powder flow through very small openings", Nucl. Technol, 52, pp.100~104 (1981)
- J. P. Mitchell, "The penetration of aerosols through fine capillaries", RAMTRANS, 1(3), pp.101~106 (1990)
- A. C. Burton, "The influence of pressure on the penetration of aerosol through fine capillaries", J. Aerosol Sci, 24(suppl. 1), pp.s559~s560 (1993)
- D. A. V. Morton, "Aerosol penetration through capillaries and leaks : experimental studies on the influence of pressure", J. Aerosol Sci, 26, pp.353~367 (1995)
- D. A. V. Morton, "Aerosol leakage through short capillaries", J. Aerosol Sci, 23(suppl. 1), pp.S27~S30 (1992)
- S. Lewis, "Solid particle penetration into enclosures", J. Hazard Mater, 43, pp.195~216 (1995)
- R. B. Mosley, "Penetration of ambient fine particles into the indoor environment", Aerosol Sci. Technol, 34(1), pp.127~136 (2001)
- J.P. Mitchell, "The Penetration of Aerosols through Fine Orifices", pp.5~17 (1992), RAMTRANS
- D. -L. Liu, "Particle penetration through building cracks", Aerosol. Sci. Technol, 37, pp.565~573 (2003)
- A. Li, "Study on particle penetration through straight, L, Z and wedge-shaped cracks in buildings", Build. Environ, 114, pp.333~343 (2017)
- A. C. K. Lai, "Penetration of fine particles through rough cracks", Atmos. Environ, 60, pp.436~443 (2012)
- E. U. Vaughan, "Simple model of plugging of ducts by aerosol deposits", Trans. ANS, 22, pp.507~ (1978)
- H. A. Morewitz, "Leakage of aerosol from containment buildings", Health Phys, 42, pp.195~ (1982)
- M. M. R. Williams, "Particle deposition and plugging in tubes and cracks(with special reference to fission product retention)", Prog. Nucl. Energy, 28, pp.1~60 (1994)
- C. F. Clement, "Aerosol penetration through capillaries and leaks : theory", J. Aerosol Sci, 26, pp.369~385 (1995)
- V. Subramanian, "Studies on chemical speciation of sodium aerosols produced in sodium fire", Nucl. Technol, 165, pp.257~269 (2009)
- P. N. Sujatha, "Experimental measurements and theoretical simulation of sodium combustion aerosol leakage through capillaries", Prog. Nucl. Energy, 18, pp.103111~ (2020)[DOI]
- "IS 456:2000, Indian Standard- Plain and Reinforced Concrete- Code of Practice (Fourth Revision)", Bureau of Indian Standard, ~ (2000)
- "IS 8112:2013, Indian Standard-Ordinary Portland Cement, 43 Grade- Specification", Bureau of Indian Standard, ~ (2013)
- "IS 1199: 2018, Fresh Concrete — Methods of Sampling, Testing and Analysis. Part 1 Sampling of Fresh Concrete", Bureau of Indian Standard, ~ (2018)
- V. Subramanian, "Initial size distribution of sodium combustion aerosols", Nucl. Technol, 160, pp.308~ (2007)
- R. Baskaran, "Aerosol test facility for fast reactor safety studies", Indian J. Pure Appl. Phys, 42, pp.873~878 (2004)
- P. N. Sujatha, "Effect of Pressure on Sodium Aerosol Leakage through Capillaries", IASTA-2016 (2016)
- P. N. Sujatha, "Theoretical simulation on evolution of suspended sodium combustion aerosols characteristics in a closed chamber", Nucl. Eng. Technol (2021)[DOI]
- J. G. Crump, "Particle wall loss rates in vessels", Aerosol. Sci. Technol, 2(3), pp.303~309 (1982)
- M. Tian, "Experimental study on the penetration efficiency of fine aerosols in thin capillaries", J. Aerosol Sci, 111, pp.26~35 (2017)
- A. Kumar, "Size evolution of sodium combustion aerosol with various RH", Aerosol Air Qual. Res, 15, pp.2270~2276 (2015)
- K. M. Haneefa, "Review of concrete performance atelevated temperature and hot sodium exposure applications in nuclear industry", Nucl. Eng. Des, 258, pp.76~88 (2013)
- T. C. Chawla, "A review of modeling concepts for sodium–concrete reactions and a model for liquid sodium transport to the unreacted concrete surface", Nucl. Eng. Des, 88, pp.85~91 (1985)