A comparative study on the effect of reactor cavity shape and location of reactor vessel on the shape of particle bed formed in pre-flooded reactor cavity using the CFD …

H Na, N Cho - Progress in Nuclear Energy, 2025 - Elsevier
Using the CFD-DEM method, numerical calculations are conducted to analyze the shape of
particle beds formed in two small-sized pre-flooded reactor cavities, aiming to understand …

Evaluation of the dryout region of heat-generating conical porous beds

H Na, H Kim, YS Lee - Progress in Nuclear Energy, 2023 - Elsevier
This study evaluates how multi-phase fluids flow and how a large volume becomes a dryout
region in a volumetrically heat-generating conical porous bed formed in the pre-flooded …

Evaluation of dryout region in a heap-like debris bed formed in an APR1400 pre-flooded reactor cavity

H Na, JH Kim, DH Shin, HC Kim, SC Kim - Annals of Nuclear Energy, 2023 - Elsevier
This study evaluates how large a debris bed becomes dryout during ex-vessel cooling in a
pre-flooded reactor cavity if a postulated severe accident occurs. It is assumed that all …

A preliminary study on concrete ablation during ex-vessel cooling in pre-flooded Westinghouse 3-loop NPP reactor cavity

H Na, DG Kang, S Pak, HJ Lee - Annals of Nuclear Energy, 2021 - Elsevier
We develop an analytical model about concrete ablation during ex-vessel cooling in a pre-
flooded cavity. The model considers the melting of dry debris bed, the formation of crust, the …

Concrete ablation depth analysis method during top water flooding ex-vessel cooling by considering phenomena in dry and flooded conditions

H Na - Progress in Nuclear Energy, 2022 - Elsevier
This study proposes a method to analyze the concrete ablation depth during top water
flooding ex-vessel cooling by considering the phenomena occurring in dry and flooded …

Analysis of concrete ablation depth by MCCI assuming top flooding condition of APR1400 NPP

H Na, S Lee, HC Kim, KT Kim - Annals of Nuclear Energy, 2021 - Elsevier
This study assesses whether the integrity of a containment maintains during ex-vessel
cooling when a molten corium spreads on a dry reactor cavity floor and then it is cooled by …

Concrete ablation depth analysis of OPR1000 NPP during top flooding ex-vessel cooling

H Na, N Cho - Nuclear Engineering and Design, 2024 - Elsevier
This study assesses the integrity of OPR1000 nuclear power plant (NPP) containment during
top flooding ex-vessel cooling in the event of a postulated severe accident. Maintaining …

Evaluation of the dryout power density of a volumetrically heat-generating three-dimensional porous bed

H Na, KB Lee, H Kim, YS Lee - Annals of Nuclear Energy, 2022 - Elsevier
A method to calculate a two-phase flow and to find the dryout region in a volumetrically heat-
generating porous bed using computational fluid dynamics (CFD) is developed. It is …

Development of the Penetration Tube Failure Analysis Program in the Lower Head of the Reactor Vessel During a Severe Accident

J Jung, HY Kim, SM An - Nuclear Technology, 2022 - Taylor & Francis
For analysis of an ex-vessel severe accident, the corium melt conditions inside the reactor
vessel are important at the time of the reactor vessel failure together with the reactor vessel …

Numerical simulation on particle sedimentation in water-filled pool using CFD-DEM method

H Na, H Kim - Annals of Nuclear Energy, 2024 - Elsevier
Numerical calculations of the bed shape formed by particles descending into a water-filled
pool have been conducted using the CFD-DEM coupling Eulerian-Lagrangian method …