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60 Years of U: Perspectives on resources, demand, and the evolving role of nuclear energy
Recent years have seen growing global interest in nuclear energy and rising confidence in the sector. For the first time since the early 2000s, there is renewed optimism about the industry’s future. This change is driven by several major factors: geopolitical developments that highlight the need for secure energy supplies, a stronger focus on resilient energy systems, national commitments to decarbonization, and rising demand for clean and reliable electricity.
Yong Jin Cho, Gyoo Dong Jeun
Nuclear Technology | Volume 158 | Number 3 | June 2007 | Pages 366-377
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT07-A3848
Articles are hosted by Taylor and Francis Online.
The header of a Canada deuterium uranium reactor (CANDU) is an important component in simulating the fuel channel behavior because the header's hydraulic behavior controls the feeder void fraction, which affects the fuel bundle coolability. In CANDU accident analyses, the liquid entrainment and vapor pull-through (off-take) phenomena should be considered when horizontal stratification is achieved inside the header. The current RELAP5 off-take model can treat only three directions: vertical upward, vertical downward, and side oriented junctions. In this study, the RELAP5 off-take model was modified and generalized by considering the geometric effect of branch angles. Based on Craya's approach, the critical height correlation was reconstructed by use of the branch line connection angle. The new model in RELAP5/CANDU could be applied to vertical upward, vertical downward, and angled branch. The verification and validation analyses for this new model were performed using separate effect test and integral effect test results. The verification and validation analyses show improved accuracy with the new model.