Estimation of Leak Rate Through Cracks in Bimaterial Pipes in Nuclear Power Plants

Nuclear Engineering and Technology

卷:48

Jin Ho Lee¹  Jai Hak Park²  Young-Jin Oh³ 

[1] Department of Mechanical and Material Assessment, Korea Institute of Nuclear Safety, 62 Gwahak-ro, Yuseong-gu, Daejeon 305-338, South Korea;

[2] Department of Safety Engineering, Chungbuk National University, 1 Chungdae-ro, Seowon-gu, Cheongju, Chungbuk 362-763, South Korea;

[3] Department of Structural Integrity and Materials, KEPCO Engineering and Construction Company, 269 Hyeoksin-ro, Gimcheon, Kyeongbuk 740-220, South Korea;

关键词: Crack;    Crack Morphology Parameter;    Flow Model;    Henry–Fauske Flow Model;    Leak Rate;    Nuclear Power Plant;    Pipe;   

DOI  :  10.1016/j.net.2016.05.005

来源: DOAJ

【 摘 要 】

The accurate estimation of leak rate through cracks is crucial in applying the leak before break (LBB) concept to pipeline design in nuclear power plants. Because of its importance, several programs were developed based on the several proposed flow models, and used in nuclear power industries. As the flow models were developed for a homogeneous pipe material, however, some difficulties were encountered in estimating leak rates for bimaterial pipes. In this paper, a flow model is proposed to estimate leak rate in bimaterial pipes based on the modified Henry–Fauske flow model. In the new flow model, different crack morphology parameters can be considered in two parts of a flow path. In addition, based on the proposed flow model, a program was developed to estimate leak rate for a crack with linearly varying cross-sectional area. Using the program, leak rates were calculated for through-thickness cracks with constant or linearly varying cross-sectional areas in a bimaterial pipe. The leak rate results were then compared and discussed in comparison with the results for a homogeneous pipe. The effects of the crack morphology parameters and the variation in cross-sectional area on the leak rate were examined and discussed.

【 授权许可】

Unknown