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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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2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
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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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Tank waste operations resume at Idaho’s IWTU
The Department of Energy’s Office of Environmental Management announced yesterday that waste processing operations have resumed at the Integrated Waste Treatment Unit (IWTU) at the Idaho National Laboratory Site. The resumption of operations follows the completion of two maintenance campaigns at the radioactive liquid waste treatment facility.
David I. Poston, Thomas F. Marcille, David D. Dixon, Benjamin W. Amiri
Nuclear Technology | Volume 166 | Number 3 | June 2009 | Pages 204-214
Technical Paper | 2007 Space Nuclear Conference / Fission Reactors | doi.org/10.13182/NT09-A8835
Articles are hosted by Taylor and Francis Online.
This paper focuses on some of the unique dynamic characteristics of compact fast-spectrum reactors. The study is limited to the characteristics that are relatively independent of how the reactor is integrated into a complete power system. Some of the well-established characteristics of compact fast-spectrum reactors are that point kinetics is generally very accurate for these systems and that temperature and burnup reactivity feedback mechanisms are relatively small and simple. Beyond this, there are two unique aspects of highly reflected fast reactors (e.g., space reactors) that do not occur in more traditional reactors. First, the neutron reflector has a very important impact on dynamic performance, and in some cases the temperature coefficient of the radial reflector is higher than that of the fuel. The thermal time constant of the reflector is much longer than that of any component in the core, which requires all reflector temperature and expansion effects to be modeled individually. Second, reflected neutrons have a much longer fission life span than in-core neutrons. In effect, this creates additional delayed neutron groups, referred to as geometric delayed neutron groups. These groups can have life spans orders of magnitude longer than neutrons that do not leave the core, and have much higher worth due to moderation. For compact beryllium reflected reactors there is also a measurable delayed group of photo-induced neutrons that result from delayed gammas. Another characteristic of compact fast-spectrum reactors is simplified control and the ability to passively handle a wide range of transients without control. Various transient analyses are presented that were performed by the Fission Reactor Integrated Nuclear Kinetics (FRINK) code, which facilitates near-term compact reactor design and development by providing a transient analysis tool. In its current state FRINK is a very simple system model, and the "system" only extends to the primary loop power removal boundary condition; however, this allows the simulation of simplified transients (e.g., loss of primary heat sink, loss of flow, etc.).