Analysis of Loss of Condenser Vacuum Accident using a Conservative Approach with a Best-Estimate Code

최적코드를 이용한 복수기진공상실 사고의 보수적 해석

Jeong, Hae-Yong

  • Received : 2015.07.02
  • Accepted : 2015.09.10
  • Published : 2015.12.31


A methodology to determine the most conservative initial condition based on random sampling of operation parameters is established, in which a best-estimate computer code is adopted to minimize the conservatism in code models. To validate the applicability of the suggested method, safety evaluation for a transient of loss of condenser vacuum in a pressurized water reactor is performed. One-hundred different initial conditions are generated by MOSAIQUE program automatically and the peak pressure for the most conservative case is determined from transient analyses. The safety margin obtained with the new approach is almost equivalent to the values determined with the existing methodologies. It is found that the time and human resources required for the safety evaluation could be reduced with the suggested approach.


Evaluation Methodology;Safety Margin;Conservatism;Safety Analysis


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Supported by : 한국연구재단