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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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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ANS joins others in seeking to discuss SNF/HLW impasse
The American Nuclear Society joined seven other organizations to send a letter to Energy Secretary Christopher Wright on July 8, asking to meet with him to discuss “the restoration of a highly functioning program to meet DOE’s legal responsibility to manage and dispose of the nation’s commercial and legacy defense spent nuclear fuel (SNF) and high-level radioactive waste (HLW).”
Chae Y. Yang, Nam Z. Cho
Nuclear Science and Engineering | Volume 101 | Number 3 | March 1989 | Pages 243-258
Technical Paper | doi.org/10.13182/NSE89-A23612
Articles are hosted by Taylor and Francis Online.
A nonlinear reactor model is developed taking into account several feedback effects, such as moderator and fuel temperatures, xenon absorption, and soluble boron concentration, through energy balance relations in the core. The resulting equation belongs to a class of nonlinear boundary value problems, and it is shown through bifurcation theory that there may exist multiple steady-state solutions for a range of parameters that correspond to various design and operating conditions. Solutions are obtained numerically for ranges of the parameters by the arc-length continuation method in combination with Newton’s method. Stability analysis is also applied to each solution to investigate whether the solution is stable or not. When the stable and unstable regions of the steady-state solutions are plotted for a wide range of the parameters, we can choose a range of the reactor design and operating conditions such that the reactor does not encounter unstable situations.