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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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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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.
H. Mösinger
Nuclear Science and Engineering | Volume 76 | Number 2 | November 1980 | Pages 89-102
Technical Paper | doi.org/10.13182/NSE80-A19443
Articles are hosted by Taylor and Francis Online.
A model for two-phase (water-vapor) flow in two-dimensional Cartesian or cylindrical coordinates is described that is implemented in the code DRIX-2D. The model includes slip between the phases and accounts for thermodynamic nonequilibrium. The code was designed as a “best-estimate” model for simulation of loss-of-coolant accidents (LOCAs) in light water reactor safety analysis. In this paper results of DRIX-2D applications are reported that can be used to assess the validity of simplified LOCA models. The main results are that both Cartesian and axisymmetric coordinates in two dimensions show considerable disadvantages as far as the pressure history in the downcomer is concerned. Yet, both models yield acceptable results concerning the gross blowdown behavior. Due to a 90-deg change in flow direction, considerable radial profiles in mass flow rate, velocity, and void fraction establish in the blowdown pipe. Nevertheless, a minor difference in the averaged mass flow rate exists only between a one- and two-dimensionally modeled blowdown pipe. A nonequilibrium state establishes at the pipe inlet in the case of subcooled vessel conditions and is maintained up to the orifice at least for pipe lengths <5m. However, the increase in mass flow rate caused by this nonequilibrium state is generally small enough for typical reactor conditions, so that an equilibrium assumption in the blowdown pipe should be appropriate for LOCA calculations.