Review of Seismic Analysis Method for Free Standing High Density Spent Fuel Racks of PWR Plant

가압경수형 발전소 자립형 고밀도 핵연료 저장랙의 지진해석 방법에 대한 검토

The paper provides a review of the analysis methods currently being used to perform seismic analysis of free standing high density spent fuel storage racks for PWR. On the basis of the analysis techniques obtained by KAERI from the design experience of Yonggwang unit 3&4 and Ulchin unit 3&4, the analysis procedure and modeling methods are discussed. The analysis of free standing fuel racks requires consideration of complex phenomena such as hydrodynamic coupling, impact through gap between fuel assembly and poison box and racks, frictional effect, rigid body sliding and tipping and etc. The present modeling of these factors is reviewed in comparison with the recommendation of regulatory group. Further improvement of analysis method and the current issues for the development are discussed.