THE REASONS OF RUPTURE OF SYSTEMS OF COOLING OF THE REACTOR AS A RESULT OF EARTHQUAKE

摘要

Methods and algorithms of calculations of quality factor of a stream of the coolant are developed. Quantitative estimations of a range of frequency of vibration - acoustical resonance between the coolant flowing through the reactor core and fuel assembly vibration in the NPP with WWER-1000 are provided. The experimental substantiation of sharp increase of intensity of vibrations at occurrence of vibration - acoustical resonance is received. Destructions at Fukushima Daiichi NPP caused by earthquake have shown that design level of seismic influences on the equipment has been exceeded. The accident demonstrated the need for stricter regulations to ensure the seismic resistance of NPP and the need to develop and implement additional anti-seismic procedures in the course of their operation. The results of the analysis of the causes of the destruction of the cooling systems of nuclear reactors from earthquakes are presented. Results should serve as a basis for developing more realistic recommendations to assess the expected level of seismic effects on the NPP.