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Division Spotlight
Fuel Cycle & Waste Management
Devoted to all aspects of the nuclear fuel cycle including waste management, worldwide. Division specific areas of interest and involvement include uranium conversion and enrichment; fuel fabrication, management (in-core and ex-core) and recycle; transportation; safeguards; high-level, low-level and mixed waste management and disposal; public policy and program management; decontamination and decommissioning environmental restoration; and excess weapons materials disposition.
Meeting Spotlight
2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
Standards Program
The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Latest News
New laws offer nuclear industry incentives for existing power plant uprates
This year, the U.S. nuclear industry received a much-needed economic boost that could help preserve operating nuclear power plants and incentivize upgrades that extend their lifespan and power output.
Signed into law in 2022, the Inflation Reduction Act offers production tax credits (PTCs) for existing nuclear power plants and either PTCs or investment tax credits (ITCs) for new carbon-free generation. These credits could make power uprates—increasing the maximum power level at which a commercial plant may operate—a much more appealing option for utilities.
Fu-Shin Wang, Lin-Wen Hu, Chin Pan
Nuclear Science and Engineering | Volume 117 | Number 1 | May 1994 | Pages 33-46
Technical Paper | doi.org/10.13182/NSE94-A13567
Articles are hosted by Taylor and Francis Online.
Natural circulation is an important passive heat-removal mechanism in both existing and next-generation light water reactors. Thermal and stability analyses are performed for a two-phase natural circulation loop. The homogeneous equilibrium model is employed to describe the two-phase flow in the loop. Subsequently, a linear stability analysis is performed in the frequency domain to establish the stability map of a natural circulation loop. The mass flow rate increases rapidly with increasing heater power until it reaches a maximum and then decreases slowly with increasing heating power. The maximum flow rate may be obtained for a riser with length and diameter two to three times that of the heater. Stability analyses indicate that in addition to the unstable region for density-wave oscillations at high power levels, there is an unstable region at low power levels. The existence of this unstable region is supported by several experimental observations. The area of the unstable region at low power levels increases with decreasing riser diameter, with increasing riser length, and with decreasing system pressure.