Nuclear Engineering and Technology

Korean Nuclear Society (한국원자력학회)
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Relative humidity prediction of a leakage area for small RCS leakage quantification by applying the Bi-LSTM neural networks

  • Sang Hyun Lee (Department of Nuclear Engineering, Chosun University) ;
  • Hye Seon Jo (Department of Nuclear Engineering, Chosun University) ;
  • Man Gyun Na (Department of Nuclear Engineering, Chosun University)
  • Received : 2023.06.06
  • Accepted : 2023.12.10
  • Published : 2024.05.25
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Abstract

In nuclear power plants, reactor coolant leakage can occur due to various reasons. Early detection of leaks is crucial for maintaining the safety of nuclear power plants. Currently, a detection system is being developed in Korea to identify reactor coolant system (RCS) leakage of less than 0.5 gpm. Typically, RCS leaks are detected by monitoring temperature, humidity, and radioactivity in the containment, and a water level in the sump. However, detecting small leaks proves challenging because the resulting changes in the containment humidity and temperature, and the sump water level are minimal. To address these issues and improve leak detection speed, it is necessary to quantify the leaks and develop an artificial intelligence-based leak detection system. In this study, we employed bidirectional long short-term memory, which are types of neural networks used in artificial intelligence, to predict the relative humidity in the leakage area for leak quantification. Additionally, an optimization technique was implemented to reduce learning time and enhance prediction performance. Through evaluation of the developed artificial intelligence model's prediction accuracy, we expect it to be valuable for future leak detection systems by accurately predicting the relative humidity in a leakage area.

Keywords

Acknowledgement

This work was supported by the Korea Institute of Energy Technology Evaluation and Planning (KETEP) grant funded by the Korea government (MOTIE) (Grant No. 20211510100050, Development of a real-time detection system for unidentified RCS leakage less than 0.5gpm).

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