ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
Division Spotlight
Operations & Power
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.
Meeting Spotlight
Utility Working Conference and Vendor Technology Expo (UWC 2024)
August 4–7, 2024
Marco Island, FL|JW Marriott Marco Island
Standards Program
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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Nuclear Science and Engineering
August 2024
Nuclear Technology
Fusion Science and Technology
Latest News
ARPA-E announces $40 million to develop transmutation technologies for UNF
The Department of Energy’s Advanced Research Projects Agency–Energy (ARPA-E) announced $40 million in funding to develop cutting-edge technologies to enable the transmutation of used nuclear fuel into less-radioactive substances. According to ARPA-E, the new initiative addresses one of the agency’s core goals as outlined by Congress: to provide transformative solutions to improve the management, cleanup, and disposal of radioactive waste and spent nuclear fuel.
Heba K. Louis
Nuclear Technology | Volume 188 | Number 1 | October 2014 | Pages 1-7
Technical Paper | Fission Reactors | doi.org/10.13182/NT13-120
Articles are hosted by Taylor and Francis Online.
The lifetime of prompt neutrons is a basic characteristic of reactors since it determines the neutron kinetics of the reactor in all transient processes. This paper focuses on calculation of the prompt neutron lifetime for pressurized water reactors (PWRs). The calculation was performed using two independent methods. The first method uses the fundamental definition of the neutron lifetime with adjoint weighting that has recently been included in MCNPX. The second method is the 1/v absorber insertion method, where a 1/v absorber such as 10B is placed uniformly throughout a nuclear reactor and the change in reactivity is calculated. This prompt neutron lifetime is then extracted from the changes in the reactivity as the 10B concentration approaches zero. The results of the two methods are compared together at two points in the operation cycle [at beginning of cycle (BOC) and at end of cycle (EOC)]. The values of the prompt neutron lifetime as calculated with MCNPX are compared to values calculated with another independent method, and the results are in reasonable agreement with each other. Also, these results compared with the PWR final safety analysis report show good agreement. In the two methods of calculation, the prompt neutron lifetime was determined to be longer at EOC when compared to that at BOC.