Computational Analysis of Large Water-to-Sodium Leak Incident in the BN-600 Steam Generator

6/05/2024 2024 - #02 Global safety, reliability and diagnostics of nuclear power installations

Perevoznikov S.V. Mikhin S.A. Kamaev A.A. Pazin G.N. Mirzeabasov O.A. Myazdrikova O.I. Borisov V.V. Pakhomov I.A.

https://doi.org/10.26583/npe.2024.2.08

The paper presents the results comparing the calculated data with the indications of water- to-sodium leak detection system and hydrodynamic parameters in the second sodium circuit, observed during the water-to-sodium leak incident in the superheater module of the BN-600 unit on January 19, 1982.

It should be noted that the reconstruction of these events in was mostly performed based on post-accident analysis data, which is rather desultory and does not describe the occurring processes accurately enough. However, this reconstruction can be used for the comparative analysis.

The calculations were performed using two codes designed to analyze the efficiency of the steam generator protection system in case of small leaks (SLEAK code) and the secondary circuit protection system against overpressure in case of large leaks (LLEAK-3C 1.0 code). The use of two calculation codes made it possible to simulate the operation of the BN-600 steam generator protection system in case of water leak in the steam generator, taking into account its leak.

Good agreement between the calculations results and post-accident analysis data was obtained.

The results of computational modeling of a real incident confirm the adequacy of physical and mathematical models, implementation of SLEAK and LLEAK-3C 1.0 codes.

References

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sodium coolant sodium-water steam generator steam generator protection system water leaks into sodium control system for small leaks large leaks

Link for citing the article: Perevoznikov S.V., Mikhin S.A., Kamaev A.A., Pazin G.N., Mirzeabasov O.A., Myazdrikova O.I., Borisov V.V., Pakhomov I.A. Computational Analysis of Large Water-to-Sodium Leak Incident in the BN-600 Steam Generator. Izvestiya vuzov. Yadernaya Energetika. 2024, no. 2, pp. 93-103; DOI: https://doi.org/10.26583/npe.2024.2.08 (in Russian).