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DOE OSTI · 23203884

Sensitivity analysis of small modular reactor mPower with ATHLET

Wang, Heliang·Wang, Xiang
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Abstract

Small modular reactor (SMR) possesses the characteristics of less radioactive source term, simpler structure, modular design and features like passive safety as well as low risk of proliferation. Developed and designed by Babcock and Wilcox, the mPower reactor is one of pronouncing small modular reactors that adopts the integrated design of the pressurized water reactor, steam generator and a built-in internal control rod drive mechanism. In this paper, the code ATHLET (Analysis of fossil-hydraulics of Leaks and Transients) is used to model the mPower reactor. At the same time, the sensitivity analysis of the core structure and geometric parameters of the pipeline loop, as well as the steady-state simulation and post-exothermic simulation are carried out depending on the given scenarios. In addition, the sensitivity analysis of pressure, temperature and mass flow in the secondary loop is performed. The results of this study will mitigate some of the frequent misunderstanding in the field and will help to better understand the design of SMR and provide basic research data for further research. However, there are limitations in the current research. Considering that the mPower is still in the conceptual design, the established model is only based on the limited public data while detailed parameters are still in myth, which leads to certain level of uncertainties in the calculation. Besides, the research is mainly on the influence of sensitivity analysis under steady state conditions. (authors)

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21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTSA CODESCOMPUTERIZED SIMULATIONPWR TYPE REACTORSSENSITIVITY ANALYSISSMALL MODULAR REACTORSSPECIFICATIONS

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Wang, Heliang, Wang, Xiang. 2022-07-01. Sensitivity analysis of small modular reactor mPower with ATHLET. https://doi.org/10.13182/physor22-37320

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