DOI: 10.1615/ICHMT.2017.CHT-7
ISBN Print: 9781-56700-4618
ISSN: 2578-5486
DEVELOPMENT OF DEVICE FOR DETECTING HELIUM LEAK FROM CANISTER -ANALYTICAL STUDY FOR TEMPERATURE BEHAVIOR DURING GAS LEAK FROM SMALL PRESSURIZED VESSEL-
SINOPSIS
Spent nuclear fuel from nuclear power reactor is stored inside a cask for a certain period of time. In a metal cask, monitoring of change in inner pressure between lids is always required. On the other hand, in a concrete cask, a loss of sealing performance of a canister, which is caused by stress corrosion cracking (SCC), is concerned in the case of the long-term storage. However, a helium leak detector is not installed to the concrete cask yet. Therefore, development of the helium leak detector is important to improve safety of concrete casks. The phenomenon that the temperature at the top of the canister (TT) decreases and the temperature of its bottom (TB) increases during helium leak from the canister has been confirmed by the experiment in the previous study. Authors have been developing the leak detector using this phenomenon. As part of the development of the device for detecting helium leak from a canister, a leak test using a small pressurized vessel simulating the canister has conducted. In order to elucidate the phenomenon observed in this test and evaluate the applicability of the result to actual equipment, test analysis was conducted. In this study, benchmark analysis was conducted by using two CFD solvers: CD-adapcoTM STAR-CCM+® (ver.11.02.010) and ANSYS® Fluent® (ver.17.1). The same values are used as physical properties and boundary conditions. And the same turbulence model is set for two kinds of analyses. An internal (Air or Helium), heat values of heaters which simulate spent fuel and an inner pressure are set as parameters. In this leak test, it was confirmed that heater temperature and TB are increased and TT is decreased when canister internal pressure is decreased. This phenomenon was reproduced by both CFD solvers. It was confirmed that both solvers can analyze this phenomenon appropriately and there is no problem with applying these CFD solvers to this phenomenon.