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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.
Peter Romstedt
Nuclear Science and Engineering | Volume 104 | Number 1 | January 1990 | Pages 1-9
Technical Paper | doi.org/10.13182/NSE90-A23696
Articles are hosted by Taylor and Francis Online.
A solution method for two-phase flow problems is presented that is very well established in numerical aerodynamics. The set of two-phase flow equations is presumed to be hyperbolic. The method solves the flow equation in its characteristic form (compatibility conditions) on a rectangular mesh. It uses the characteristic directions only to determine how the numerical solution depends on the upstream and downstream fluid flow states, in contrast to the method of characteristics. This results in a particular choice of backward and forward differences to approximate the spatial derivatives and yields a stable numerical scheme. The method works on a simple discrete mesh and does not need a staggered mesh for stability, as is widely used for two-phase flow calculations. Thereby, numerical diffusion is reduced and less computer time is needed because the equations of state are only evaluated at half the discrete points. The method is compared to a staggered mesh second-order method by solving different steady-state and transient two-phase flow problems (homogeneous equilibrium model).