Izvestiya vuzov. Yadernaya Energetika

The peer-reviewed scientific and technology journal. ISSN: 0204-3327

Temperature Conditions in the RBMK Spent Fuel Storage Pool in the Event of Disturbances in its Cooling Mode

11/19/2020 2020 - #04 Nuclear power plants

Hakobyan D.A. Slobodchuk V.I.

DOI: https://doi.org/10.26583/npe.2020.4.02

UDC: 629.039.58

The problems of reprocessing and long-term storage of spent nuclear fuel (SNF) at nuclear power plants with RBMK-type reactors have not been fully resolved so far. As a result, nuclear power plants are forced to search for new options of temporary storage of SNF. One of the possible temporary solutions to the problem is compacted SNF storage in the reactor spent fuel storage pool (SFSP). As the number of spent fuel assemblies (SFA) in the SFSP increases, a greater amount of heat is released. In addition, it is necessary to take into account the fact that provision should be made for some additional storage space in the pool where fuel assemblies can be placed in an emergency situation. The paper presents the results of a numerical simulation of the temperature regime in the spent fuel storage pool both for storage of compacted SFAs and for emergency unloading of fuel assemblies. Several types of disturbances in the normal SFSP cooling mode are considered, including partial loss of cooling water and uncovering of SFA. The simulation was performed using the ANSYS CFX code. The time it takes for the water to reach the boiling point is estimated, as well as the time over which the fuel cladding is heated to 650°C. The most critical conditions are observed in the compartment for emergency unloading of fuel assemblies. The results obtained make it possible to estimate the time that personnel have to restore the cooling mode of the spent fuel storage pool before the maximum water and SFA temperature is reached.

References

  1. Bernd S.J. Status of the spent fuel in the reactor buildings of Fukushima Daiichi 1-4. Nuclear Engineering and Design. 2015, v. 283, pp. 2-7.
  2. Song J.H., Kim T.W. Severe accident issues raised by the Fukushima accident and improvements suggested. Nuclear Engineering and Technology. 2014, v. 46, pp. 207-216.
  3. Kaliatka A. et al. Analysis of the processes in spent fuel pools in case of loss of heat removal due to water leakage. Science and Technology of Nuclear Installations. 2013, no. 3, pp. 1-11.
  4. Partmann C., Schuster C., Hurtado A. Experimental investigation of the thermal hydraulics of a spent fuel pool under loss of active heat removal conditions. Nuclear Engineering and Design. 2018, v. 330, pp. 480-487.
  5. Cheng-Lun Yu. Numerical study on hydrodynamic and thermal characteristics of spent fuel pool. Annals of Nuclear Energy. 2018, v. 119, pp. 139-147.
  6. Hung T.-C. et al. The development of a three-dimensional transient CFD model for predicting cooling ability of spent fuel pools. Applied Thermal Engineering. 2013, v. 50, pp. 496-504.
  7. Wang D. et al. Study of Fukushima Daiichi nuclear power station unit 4 spent-fuel pool. Nuclear Technology. 2012, v. 180, pp. 205-215.
  8. Gauntt R.O. et al. MELCOR computer code manuals. 2000, Report NUREG/CR6119, U.S. Nuclear Regulatory Commission, Washington, DC, USA.
  9. Barto A. et al. Consequence study of a beyond-design-basis earthquake affecting the spent fuel pool for a U.S. Mark I boiling water reactor. 2013, Report SECY130112 Enclosure1 (ADAMS accession no. ML13256A342), U.S. Nuclear Regulatory Commission, Washington, DC, USA.
  10. Chen S.R. et al. CFD simulating the transient thermal–hydraulic characteristics in a 17×17 bundle for a spent fuel pool under the loss of external cooling system accident. Annals of Nuclear Energy. 2014, v. 73, pp. 241-249.
  11. Ahn K.I., Shin J.U., Kim W.T. Severe accident analysis of plant-specific spent fuel pool to support a SFP risk and accident management. Annals of Nuclear Energy. 2016, v. 89, pp. 70-83.
  12. Ogino M. Analysis of fuel heat-up in a spent fuel pool during a LOCA. 2012. In: Technical Workshop on the Accident of TEPCO’s Fukushima Daiichi NPS, July 23-24. 2012, Tokyo, Japan.
  13. Jackel B. Spent fuel pool boil down calculations with MELCOR 1.8.6. 2013. In: Fifth European MELCOR User Group Meeting, May 2-3. 2013, Stockholm, Sweden.
  14. Cheng-Lun Yu. Numerical study on hydrodynamic and thermal characteristics of spent fuel pool. Annals of Nuclear Energy. 2018, v. 119, pp. 139-147.
  15. Calculation of the temperature regime of water in the SFP and justification of explosion safety when handling uranium-erbium fuel. Report 01416253TX. Moscow. OJSC Atomenergoproekt Publ., 2011 (in Russian).
  16. ANSYS CFX. User’s Guide. ANSYS Inc., 2011, 368 p.
  17. Chirkin V.S. Thermophysical properties of nuclear materials. Handbook. Moscow. Atomizdat Publ., 1968, 484 p. (in Russian).
  18. Rivkin S.L., Alexandrov A.A. Thermodynamic properties of water and water steam. Handbook. Moscow. Energoatomizdat Publ., 1984, 80 p. (in Russian).
  19. Kirillov P.L., Bobkov V.P., Zhukov A.V., Yur’ev Yu.S. Handbook on thermohydraulic calculations in nuclear power industry. Edited by P.L. Kirillov. Vol. 1: Thermohydraulic processes in nuclear power plants. Moscow. IzdAT Publ., 2010, 771 p. (in Russian).
  20. Engineering – Handbook. Available at: http://fast-const.ru/articles.php?article_id=20 (accessed May 20, 2019) (in Russian).
  21. ProfProkat – Handbook of Metals. Available at: http://profprokat.ru/content/view/167/8/ (accessed May 20, 2019) (in Russian).

nuclear power plant reactor spent fuel storage pool spent nuclear fuel temperature conditions