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Decommissioning & Environmental Sciences
The mission of the Decommissioning and Environmental Sciences (DES) Division is to promote the development and use of those skills and technologies associated with the use of nuclear energy and the optimal management and stewardship of the environment, sustainable development, decommissioning, remediation, reutilization, and long-term surveillance and maintenance of nuclear-related installations, and sites. The target audience for this effort is the membership of the Division, the Society, and the public at large.
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2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
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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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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.
E. V. Depiante
Nuclear Science and Engineering | Volume 113 | Number 3 | March 1993 | Pages 251-263
Technical Paper | doi.org/10.13182/NSE93-A24493
Articles are hosted by Taylor and Francis Online.
Part of the reactor design process is performance evaluation according to predefined criteria, including reactor stability behavior under different conditions. This work focuses on the stability characterization of a reactor system with feedback under low reactor power, low reactor coolant flow conditions. Such conditions might be encountered, for example, after a loss of flow without scram in some passively safe reactor designs. Algebraic and frequency stability-criteria-based methods are developed to find stability regions, stability boundary surface in system parameter space, and frequency of oscillation at oscillatory instability boundaries. Models are developed for the reactor, its detailed thermal-hydraulic reactivity feedback path associated with coolant outlet temperature, and decay heat. Developed stability analysis tools are applied to the system model. A unique aspect is the assessment of the influence of decay heat on stability. Other selected parameters are the following: temperature coefficient of reactivity, reactor coolant flow, and natural-circulation flow. The result is a stability boundary surface in four-dimensional system parameter space and its associated frequency of oscillation surface. Adopting model parameter values from two reactors results in system parameters within the stable region. Conditions for system parameters to remain in the stable region are identified.