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The division provides a forum for focused technical dialogue on thermal hydraulic technology in the nuclear industry. Specifically, this will include heat transfer and fluid mechanics involved in the utilization of nuclear energy. It is intended to attract the highest quality of theoretical and experimental work to ANS, including research on basic phenomena and application to nuclear system design.
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June 15–18, 2025
Chicago, IL|Chicago Marriott Downtown
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Latest News
Federal Power Act amendments focus on grid reliability
Fedorchak
North Dakota’s sole member of the U.S. House of Representatives, Republican freshman Congresswoman Julie Fedorchak, has introduced the Baseload Reliability Protection Act.
The bill aims to “amend the Federal Power Act to prohibit retirements of baseload electric generating units in any area that is served by a Regional Transmission Organization or an Independent System Operator and that the North American Electric Reliability Corporation [NERC] categorizes as at elevated risk or high risk of electricity supply shortfalls, and for other purposes.”
A summary of the legislation is available on Fedorchak’s House website.
Amendments: The Baseload Reliability Protection Act would amend the Federal Power Act in the following ways:
M. E. Rising, A. K. Prinja, P. Talou
Nuclear Science and Engineering | Volume 175 | Number 2 | October 2013 | Pages 188-203
Technical Paper | doi.org/10.13182/NSE12-93
Articles are hosted by Taylor and Francis Online.
The polynomial chaos expansion-stochastic collocation method (PCE-SCM) is demonstrated to be a computationally efficient approach for propagating nuclear data uncertainties evaluated for the prompt fission neutron spectra (PFNS) of n + 235U and n + 239Pu fission reactions through two fast neutron critical benchmark experiments. A principal component decomposition of the PFNS covariance matrices yields an efficient representation of the uncertainty in terms of two to four random variables. Both normal and uniform distributions are considered for these random variables, and the random output variables (angular flux and k-eigenvalue) are expressed in terms of Hermite and Legendre chaos expansions, respectively. Tensor product Hermite and Legendre Gauss quadrature sets, respectively, are used to relate the deterministic chaos expansion coefficients to solutions of independent transport k-eigenvalue problems, and the resulting polynomial chaos expansion provides a complete statistical characterization of the uncertainty in the output variables. Direct random sampling of the PFNS followed by repeated solution of the transport problem to create an ensemble of solutions is used to benchmark results obtained from the PCE-SCM implementation. Both direct random sampling and the PCE-SCM implementation yield comparable results where, for the Jezebel and Lady Godiva critical assemblies, the calculated uncertainties in keff resulting from the PFNS propagated uncertainties are found to be of the same order or larger than reported experimental measurement uncertainties, respectively. The PCE-SCM implementation results obtained require orders of magnitude less computational resources compared with the direct random sampling approach.