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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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DOE issues new NEPA rule and procedures—and accelerates DOME reactor testing
Meeting a deadline set in President Trump’s May 23 executive order “Reforming Nuclear Reactor Testing at the Department of Energy,” the DOE on June 30 updated information on its National Environmental Policy Act (NEPA) rulemaking and implementation procedures and published on its website an interim final rule that rescinds existing regulations alongside new implementing procedures.
J. Michael Doster, Mark A. Holmes
Nuclear Science and Engineering | Volume 124 | Number 1 | September 1996 | Pages 125-144
Technical Paper | doi.org/10.13182/NSE96-A24229
Articles are hosted by Taylor and Francis Online.
A standard model for describing time-dependent two-phase flows is the so-called six-equation or two-fluid model, where mass, energy, and momentum equations are considered for each phase. It is well known that the single-pressure form of this model can contain complex characteristics and is therefore ill posed. This ill-posedness has been blamed for numerical instabilities that have at times been observed when finite difference solutions of these equations have been attempted. One method to render the characteristics real is to include viscous terms. The numerical implications of adding viscous terms to the six-equation model are considered, and the potential impact of these implications on the stability of the finite difference solution is evaluated.