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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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Latest News
Powering the future: How the DOE is fueling nuclear fuel cycle research and development
As global interest in nuclear energy surges, the United States must remain at the forefront of research and development to ensure national energy security, advance nuclear technologies, and promote international cooperation on safety and nonproliferation. A crucial step in achieving this is analyzing how funding and resources are allocated to better understand how to direct future research and development. The Department of Energy has spearheaded this effort by funding hundreds of research projects across the country through the Nuclear Energy University Program (NEUP). This initiative has empowered dozens of universities to collaborate toward a nuclear-friendly future.
Andreas Pautz, Adolf Birkhofer
Nuclear Science and Engineering | Volume 145 | Number 3 | November 2003 | Pages 299-319
Technical Paper | doi.org/10.13182/NSE03-A2385
Articles are hosted by Taylor and Francis Online.
A new neutron transport code for time-dependent analyses of nuclear systems has been developed. The code DORT-TD is based on the well-known Discrete Ordinates code DORT, which solves the steady-state neutron transport equation in two dimensions for an arbitrary number of energy groups and standard regular geometries. For the implementation of time-dependence, a fully implicit, unconditionally stable time integration scheme was employed to minimize errors due to temporal discretization. This requires several modifications to the transport equation and the extensive use of sophisticated acceleration mechanisms. The convergence criteria for fluxes and fission densities had to be strongly tightened to ensure the reliability of results. We also allowed for cross sections varying with time to couple neutronics and thermal hydraulics calculations. The neutronics code was finally applied to a research reactor to show its capabilities for both slow and fast transients.