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Aerospace Nuclear Science & Technology
Organized to promote the advancement of knowledge in the use of nuclear science and technologies in the aerospace application. Specialized nuclear-based technologies and applications are needed to advance the state-of-the-art in aerospace design, engineering and operations to explore planetary bodies in our solar system and beyond, plus enhance the safety of air travel, especially high speed air travel. Areas of interest will include but are not limited to the creation of nuclear-based power and propulsion systems, multifunctional materials to protect humans and electronic components from atmospheric, space, and nuclear power system radiation, human factor strategies for the safety and reliable operation of nuclear power and propulsion plants by non-specialized personnel and more.
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International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver Downtown
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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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Argonne’s METL gears up to test more sodium fast reactor components
Argonne National Laboratory has successfully swapped out an aging cold trap in the sodium test loop called METL (Mechanisms Engineering Test Loop), the Department of Energy announced April 23. The upgrade is the first of its kind in the United States in more than 30 years, according to the DOE, and will help test components and operations for the sodium-cooled fast reactors being developed now.
D. G. Cacuci, P. J. Maudlin, C. V. Parks
Nuclear Science and Engineering | Volume 83 | Number 1 | January 1983 | Pages 112-135
Technical Paper | doi.org/10.13182/NSE83-A17994
Articles are hosted by Taylor and Francis Online.
A recently developed sensitivity theory for nonlinear systems with responses defined at critical points, e.g., maxima, minima, or saddle points, of a function of the system's state variables and parameters is applied to a protected transient with scram on high-power level in the Fast Flux Test Facility. The single-phase segment of the fast reactor safety code MELT-IIIB is used to model this transient. Two responses of practical importance, namely, the maximum fuel temperature in the hot channel and the maximum normalized reactor power level, are considered. For the purposes of sensitivity analysis, a complete characterization of such responses requires consideration of both the numerical value of the response at the maximum, and the location in phase space where the maximum occurs. This is because variations in the system parameters alter not only the value at this maximum but also alter the location of the maximum in phase space. Expressions for the sensitivities of the numerical value of each maximum-type response and expressions for the sensitivities of the phase-space location at which the respective maximum occurs are derived in terms of adjoint functions. The adjoint systems satisfied by each of these adjoint functions are derived and solved. It is shown that the complete sensitivity analysis of each maximum-type response requires (a) the computation of as many adjoint functions as there are nonzero components of the maximum in phase space, and (b) the computation of one additional adjoint function for evaluating the sensitivities of the numerical value of the response. The same computer code can be used to calculate all the required adjoint functions. Once these adjoint functions are available, the sensitivities to all possible variations in the system parameters are obtained by quadratures. The sensitivities obtained by this efficient method are used to predict both changes in the numerical values of these maximum-type responses, and the new phase-space location at which the perturbed maxima occur when the system parameters are varied. These predictions are shown to agree well with direct recalculations using perturbed parameter values.
