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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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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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Latest News
First astatine-labeled compound shipped in the U.S.
The Department of Energy’s National Isotope Development Center (NIDC) on March 31 announced the successful long-distance shipment in the United States of a biologically active compound labeled with the medical radioisotope astatine-211 (At-211). Because previous shipments have included only the “bare” isotope, the NIDC has described the development as “unleashing medical innovation.”
Amir N. Nahavandi, Richard F. von Hollen
Nuclear Science and Engineering | Volume 20 | Number 4 | December 1964 | Pages 392-413
Technical Paper | doi.org/10.13182/NSE64-A20982
Articles are hosted by Taylor and Francis Online.
A one-dimensional space-dependent dynamic analysis of boiling water reactors, for direct, indirect or dual cycle systems with forced or natural circulation is presented. The analytical model consists of space-dependent neutron kinetics equations for the reactor core, and flow-conservation equations for the reactor coolant system developed in terms of length along the flow path and time. The resulting set of non-linear partial differential equations is expressed spatially in finite-difference form and integrated numerically in time to obtain the space- and time-dependent system variables. The effect of system-pressure variation is neglected. The mathematical model and numerical procedures employed in this study are verified against available test data from the Levy and Beckjord experimental boiling loop. Analytical predictions of the threshold of instability and the frequency of oscillations are shown to be in agreement with the test data. Studies of the uncontrolled and controlled behavior of a 110-MWe direct cycle boiling water nuclear power station confirm that, in contrast with natural-circulation loops, forced-circulation boiling systems have a high degree of hydrodynamic stability. However, an inappropriate selection of control-system parameters may induce nuclear power instability in both natural- and forced-circulation plants. The theoretical approach presented maybe successfully employed as a powerful tool for the determination of the system stability, as well as for evaluation of the degree of effectiveness and relative merits of various system power-control techniques.