Application of the Dynamic Probabilistic Assessment Method for Predicting Possible Accidents at NPPs with VVER-1200 Reactors
DOI:
https://doi.org/10.24160/1993-6982-2026-4-144-152Keywords:
NPP safety, computer technologies, computer codes, DPSAAbstract
The article considers the principles of the dynamic probabilistic safety assessment (DPSA) method using the global optimum search approach – a genetic algorithm (GA). The DPSA method with the use of GA is implemented in the Nuclear Plant Optimizer (NPO) software, which employs parallel computing mode and connected with the RELAP5 computer code. The aim of the work is to demonstrate the possibility of combining the GA and DPSA technologies (GA–DPSA) for NPP safety analysis purposes. To demonstrate the proposed procedure, accidents involving guillotine break of the main coolant pipeline (MCP) and a small-break leak of the MCP cold leg for a VVER-1200 reactor were simulated. The thermal-hydraulic model was implemented using the RELAP5 best-estimate computer code. The computation results have revealed accident progression scenarios in which earlier actuation of safety systems is less favorable in terms of safety than their later actuation. The proposed methodology makes it possible to identify hypothetical accidents that have not been revealed as yet, and can be used for further studies on assessing the NPP safety.
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Для цитирования: Ушаков Д.Ю., Воробьев Ю.Б., Четвериков А.Е. Применение метода динамического вероятностного анализа для прогнозирования возможных аварий на атомных электростанциях с ВВЭР-1200 // Вестник МЭИ. 2026. № 4. С. 144—152. DOI: 10.24160/1993-6982-2026-4-144-152
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Конфликт интересов: авторы заявляют об отсутствии конфликта интересов
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8. Belhadj M., Hassan M., Aldemir T. On the Need for Dynamic Methodologies in Risk and Reliability Studies. Reliability Eng. & Syst. Safety. 1992;38(3):219—236.
9. Coppit D., Sullivan K.J., Dugan J.B. Formal Semantics of Models for Computational Engineering: a Case Study on Dynamic Fault Trees. Proc. XI Intern. Symp. Software Reliability Eng. San Jose, 2000:270—282.
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For citation: Ushakov D.Yu., Vorobyev Yu.B., Chetverikov A.E. Application of the Dynamic Probabilistic Assessment Method for Predicting Possible Accidents at NPPs with VVER-1200 Reactors. Bulletin of MPEI. 2026;4:144—152. (in Russian). DOI: 10.24160/1993-6982-2026-4-144-152
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Conflict of interests: the authors declare no conflict of interest
