Conference Paper

Improving Swarm Region Modeling in Pool Scrubbing Through a Mean Bubble Size Approach

November 2024

Conference: The 13th Korea-Japan Symposium on Nuclear Thermal Hydraulics and Safety
At: Seoul, South Korea

Authors:

FNC Technology

Independent Researcher

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The process of pool scrubbing is crucial for managing severe nuclear reactor accidents. However, there are significant uncertainties regarding the retention capacity of fission products. The effectiveness of pool scrubbing has a direct impact on the source term. However, current modeling and prediction capabilities are limited due to conservative assumptions in pool scrubbing codes, such as SPARC-90 (Owczarski and Burk, 1991). Enhancing current models by incorporating detailed local information and new correlations from CFD analyses can help improve the Decontamination Factor (DF) estimation. One notable shortcoming of current pool scrubbing models is the inadequate representation of bubble dynamics. Existing models often use constant diameter assumptions, which fail to capture the dynamic nature of bubble size variations, thereby compromising the effectiveness of pool scrubbing systems. This study aims to develop a new bubble size model for the swarm rise region to improve the accuracy and reliability of pool scrubbing models.

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