The applicability of cfd to simulate and study the mixing process and the thermo-hydraulic consequences of a main steam line break in PWR model

I. Farkas, Ezddin Hutli, Tatiana Farkas, Antal Takacs, Ivan Toth, Attila Guba

Research output: Contribution to journalArticle


This paper focuses on the validation and applicability of CFD to simulate and analyze the thermo-hydraulic consequences of a main steam line break. Extensive validation data come from experiments performed using the Rossendorf coolant mixing model facility. For the calculation, the range of 9 to 12 million hexahedral cells was constructed to capture all details in the interrogation domain in the system. The analysis was performed by running a time-dependent calculation, Detailed analyses were made at different cross-sections in the system to evaluate not only the value of the maximum and minimum temperature, but also the location and the time at which it occurs during the transient which is considered to be indicator for the quality of mixing in the system. CFD and experimental results were qualitatively compared; mixing in the cold legs with emergency core cooling systems was overestimated. This could be explained by the sensitivity to the boundary conditions. In the downcomer, the experiments displayed higher mixing: by our assumption this related to the dense measurement grid (they were not modelled). The temperature distribution in the core inlet plane agreed with the measurement results. Minor deviations were seen in the quantitative comparisons: the maximum temperature difference was 2°C.

Original languageEnglish
Pages (from-to)3025-3036
Number of pages12
JournalThermal Science
Issue number6
Publication statusPublished - Jan 1 2017



  • Cold-leg
  • Coolant
  • Density
  • Emergency core cooling
  • Loss-of-coolant accident
  • Main steam line break
  • Mixing
  • Pressurized water reactor
  • Reactor pressure vessel
  • Temperature

ASJC Scopus subject areas

  • Renewable Energy, Sustainability and the Environment

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