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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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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
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.”
Alexander Agung, Danny Lathouwers, Tim H. J. J. van der Hagen, Hugo van Dam, Christopher C. Pain
Nuclear Technology | Volume 165 | Number 2 | February 2009 | Pages 133-144
Technical Paper | Fission Reactors | doi.org/10.13182/NT09-A4081
Articles are hosted by Taylor and Francis Online.
A new design of a fluidized bed has been proposed and it has been shown that under steady condition the reactor is able to produce power up to 120 MW. To study the behavior of the reactor under transient conditions as well as its stability, a model describing the coupling of neutronics, thermal hydraulics, and fluidization is applied. The objective of this study is to comprehend whether the reactor is stable under its operational range. Further, knowledge of the extent of operational parameters under large perturbations is necessary for a safe operation.The stability of the system is investigated by numerical means and is performed by linearizing and perturbing the system around its equilibrium points to form Jacobian matrices. The resulting matrices are further used to obtain the eigenvalues of the system. The system is investigated under variation of mass flow rate, and it is found that within the operational range the eigenvalues are located in the negative part of the phase plane, implying linear stability. Further, the calculated decay ratios indicate a strongly damped system.Simulations of transient conditions are performed, namely, a step change in coolant flow rate and inlet temperature, representing situations that might occur in real operations of the reactor. The coolant flow rate is varied by ±1 kg/s and the inlet gas temperature is varied by ±10 K from their steady state of 33 kg/s and 543 K, respectively. Another transient is also simulated, i.e., a transient related to noise resulting from stochastic movements of the fuel particles. For this purpose, an additional term is included in the reactivity feedback and modeled as a time-dependent external reactivity. Magnitude of the variance for this simulation is obtained from the preceding static calculations. These simulations show that the total power of the reactor may fluctuate and reach high values. However, the fuel temperature, thanks to passive reactivity feedback, is well below safety limits at all times.