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Education, Training & Workforce Development
The Education, Training & Workforce Development Division provides communication among the academic, industrial, and governmental communities through the exchange of views and information on matters related to education, training and workforce development in nuclear and radiological science, engineering, and technology. Industry leaders, education and training professionals, and interested students work together through Society-sponsored meetings and publications, to enrich their professional development, to educate the general public, and to advance nuclear and radiological science and engineering.
Meeting Spotlight
Conference on Nuclear Training and Education: A Biennial International Forum (CONTE 2025)
February 3–6, 2025
Amelia Island, FL|Omni Amelia Island Resort
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
Senate committee hears from energy secretary nominee Chris Wright
Wright
Chris Wright, president-elect Trump’s pick to lead the U.S. Department of Energy, spent hours today fielding questions from members of the U.S. Senate’s committee on Energy and Natural Resources.
During the hearing, Wright—who’s spent most of his career in fossil fuels—made comments in support of nuclear energy and efforts to expand domestic generation in the near future. Asked what actions he would take as energy secretary to improve the development and deployment of SMRs, Wright said: “It’s a big challenge, and I’m new to government, so I can’t list off the five levers I can pull. But (I’ve been in discussions) about how to make it easier to research, to invest, to build things. The DOE has land at some of its facilities that can be helpful in this regard.”
M. Ionescu-Bujor, D. G. Cacuci
Nuclear Science and Engineering | Volume 136 | Number 1 | September 2000 | Pages 85-121
Technical Paper | doi.org/10.13182/NSE136-85
Articles are hosted by Taylor and Francis Online.
This work presents results that illustrate the validation of the Adjoint Sensitivity Model (ASM-REL/TF) corresponding to the two-fluid model with noncondensable(s) used in RELAP5/MOD3.2. This validation has been carried out by using sample problems involving (a) a liquid phase only, (b) a gas phase only, and (c) a two-phase mixture (of water and steam). Thus, the "Two-Loops with Pumps" sample problem supplied with RELAP5/MOD3.2 has been used to verify the accuracy and stability of the numerical solution of the ASM-REL/TF when only the liquid phase is present. Furthermore, the "Edwards Pipe" sample problem, also supplied with RELAP5/MOD3.2, has been used to verify the accuracy and stability of the numerical solution of the ASM-REL/TF when both (i.e., liquid and gas) phases are present. In addition, the accuracy and stability have been verified of the numerical solution of the ASM-REL/TF when only the gas phase is present by using modified "Two-Loops with Pumps" and the "Edwards Pipe" sample problems in which the liquid- and two-phase fluids, respectively, were replaced with pure steam. The results obtained for these sample problems depict typical sensitivities of junction velocities and volume-averaged pressures to perturbations in initial conditions and indicate that the numerical solution of the ASM-REL/TF is as robust, stable, and accurate as the original RELAP5/MOD3.2 calculations.This work also illustrates the role that sensitivities of the thermodynamic properties of water play for sensitivity analysis of thermal-hydraulic codes for light water reactors. The well-known 1993 ASME Steam Tables are used to present typical analytical and numerical results for sensitivities of the thermodynamic properties of water to the numerical parameters that appear in the mathematical formulation of these properties. Particularly highlighted are the very large sensitivities displayed by the specific isobaric fluid and gas heat capacities Cpf and Cpg, respectively; the specific fluid enthalpy hf; the specific gas volume Vg; the volumetric expansion coefficient for gas g; and the isothermal coefficient for gas kg. The dependence of g and kg on the most sensitive parameters turns out to be nonlinear, while the dependence of Cpf, Cpg, hf, and Vg on the most sensitive parameters turns out to be linear, so the respective sensitivities predict exactly the effects of variations in the respective parameters. On the other hand, the sensitivities of the specific fluid volume Vf, the volumetric expansion coefficient for fluid f, the specific gas enthalpy hg, and the isothermal coefficient of compressibility for fluid kf to the parameters that appear in their respective mathematical formulas are quite small. Finally, it is noted that such deterministically calculated sensitivities can be used to rank the respective parameters according to their importance, to assess the effects of nonlinearities and, more generally, to perform comprehensive sensitivity/uncertainty analyses of thermal-hydraulic codes that use a water substance as the working fluid.
