Unstructured mesh-based multi-physics reactor transient simulation with iMC code

Kim, Hyeon Tae; Kim, Yonghee

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DOE OSTI · 23178748

Unstructured mesh-based multi-physics reactor transient simulation with iMC code

Kim, Hyeon Tae·Kim, Yonghee

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Abstract

In this study, we present a time-dependent Monte Carlo simulation result about a complex fuel-loaded light water reactor system with thermal-hydraulic feedback using the KAIST iMC code. The intra-pin temperature distribution is calculated based on Monte Carlo-tallied detailed power distribution and the finite element heat transfer method. The temperature effect of fuel, absorber, and coolant are adequately reflected into the dynamic response by the on-the-fly Doppler broadened cross-section correction. For the time-dependent Monte Carlo transport simulation, the predictor-corrector quasi-static Monte Carlo method is used for this study. We tested the coupled analysis framework with a 17-by-17 fuel assembly loaded with the centrally-shielded burnable absorber (CSBA) fuel element. The temperature feedback effect on the material cross-section and the moderator density incurred negative reactivity in response to the external positive reactivity insertion, showing the inherent stability of the reactor system. The pin-wise power and temperature change during the system transient are presented and discussed. (authors)

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21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS COMPUTERIZED SIMULATION COUPLING FLUID FLOW HEAT TRANSFER I CODES REACTOR KINETICS EQUATIONS TRANSIENTS WATER COOLED REACTORS

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Kim, Hyeon Tae, Kim, Yonghee. 2022-07-01. Unstructured mesh-based multi-physics reactor transient simulation with iMC code. https://www.osti.gov/biblio/23178748

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