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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Deep Space: The new frontier of radiation controls
In commercial nuclear power, there has always been a deliberate tension between the regulator and the utility owner. The regulator fundamentally exists to protect the worker, and the utility, to make a profit. It is a win-win balance.
From the U.S. nuclear industry has emerged a brilliantly successful occupational nuclear safety record—largely the result of an ALARA (as low as reasonably achievable) process that has driven exposure rates down to what only a decade ago would have been considered unthinkable. In the U.S. nuclear industry, the system has accomplished an excellent, nearly seamless process that succeeds to the benefit of both employee and utility owner.
Tom Elicson, Hugh Luo, David Luxat (Jensen Hughes), Lajos Tarczal (Paks Nuclear Power Plant), Tom Kindred (EPRI)
Proceedings | Advances in Thermal Hydraulics 2018 | Orlando, FL, November 11-15, 2018 | Pages 365-378
The MAAP v5.03 computer program was modified to incorporate the unique features of the VVER plant design to provide a state-of the-art severe accident analysis code for the VVER plants. The MAAP5-VVER code is applicable to the VVER-440, VVER-1000, and VVER-1200 plant designs and is capable of accurately modeling scenarios with in-vessel melt retention (IVMR), which is a crucial VVER accident management strategy, and PRISE accidents (large primary-to-secondary leaks) which are key contributors to plant risk. The MAAP5-VVER code version is intended to be applied to accident management analyses as well as Level 1 and Level 2 PRA analyses.
To ensure that the MAAP5-VVER code adequately addresses phenomena and capabilities important to the expected VVER applications, the MAAP5-VVER code is undergoing verification and validation (V&V) testing prior to final code release. The V&V test plan is designed to provide complete coverage of the MAAP5-VVER specific models and important modeling capabilities. Additionally, the validation exercises consist of data for both the VVER-440 and VVER-1000 plants designs obtained from scaled experiments, full scale plant tests, and other detailed code calculations.
This paper provides an overview of the MAAP5-VVER modeling capabilities, discusses the MAAP5-VVER V&V testing program, and presents preliminary results for a benchmark against the IAEA-SPE-3 test performed at the PMK-2 scaled test facility.
