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Members focus on the dissemination of knowledge and information in the area of power reactors with particular application to the production of electric power and process heat. The division sponsors meetings on the coverage of applied nuclear science and engineering as related to power plants, non-power reactors, and other nuclear facilities. It encourages and assists with the dissemination of knowledge pertinent to the safe and efficient operation of nuclear facilities through professional staff development, information exchange, and supporting the generation of viable solutions to current issues.
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2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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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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Commercial nuclear innovation "new space" age
In early 2006, a start-up company launched a small rocket from a tiny island in the Pacific. It exploded, showering the island with debris. A year later, a second launch attempt sent a rocket to space but failed to make orbit, burning up in the atmosphere. Another year brought a third attempt—and a third failure. The following month, in September 2008, the company used the last of its funds to launch a fourth rocket. It reached orbit, making history as the first privately funded liquid-fueled rocket to do so.
Michael L. Fensin, John S. Hendricks, Samim Anghaie
Nuclear Technology | Volume 164 | Number 1 | October 2008 | Pages 3-12
Technical Paper | Icapp '06 | doi.org/10.13182/NT08-A4003
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As advanced reactor concepts challenge the accuracy of current modeling technologies, a higher-fidelity depletion calculation is necessary to model time-dependent core reactivity properly for accurate cycle length and safety margin determinations. The recent integration of CINDER90 into the MCNPX Monte Carlo radiation transport code provides a completely self-contained Monte Carlo-linked depletion capability. Two advances have been made in the latest MCNPX capability based on problems observed in prereleased versions: continuous-energy collision density tracking and adequate fission yield selection.Prereleased versions of the MCNPX depletion code calculated the reaction rates for (n,2n), (n,3n), (n,p), and (n,) by matching the MCNPX steady-state 63-group flux with 63-group cross sections inherent in the CINDER90 library and then collapsing to one-group collision densities for the depletion calculation. The accuracy of this procedure is therefore dictated by the adequacy of the 63-group energy structure of the cross-section set to accurately capture the spectrum of a specific model. Different types of models would therefore require different types of cross-section energy group structure. MCNPX 2.6.A eliminates this dependency by using the continuous-energy reaction rates determined during the MCNPX steady-state calculation to calculate energy-integrated collision rates to be used by CINDER90.MCNPX 2.6.A now also determines the proper fission yield to be used by the CINDER90 code for the depletion calculation. The CINDER90 code offers a thermal, fast, and high-energy fission yield for each fissile isotope contained in the CINDER90 data file. MCNPX 2.6.A determines which fission yield to use for a specified problem by calculating the integral fission rate for the defined energy boundaries (thermal, fast, and high energy), determining which energy range contains the majority of fissions, and then selecting the appropriate fission yield for the energy range containing the majority of fissions.The MCNPX depletion capability enables complete, relatively easy-to-use depletion calculations in a single Monte Carlo code. This study focuses on the methodology development of the two improvements described here. Further improvements are under development to enhance the usefulness of this new capability.