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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. A. Favorite, W. M. Stacey, Jr.
Nuclear Science and Engineering | Volume 126 | Number 3 | July 1997 | Pages 282-292
Technical Paper | doi.org/10.13182/NSE97-A24481
Articles are hosted by Taylor and Francis Online.
A new variational estimate for dynamic reactivity that accounts for delayed neutron holdback is introduced and adapted for use with the improved quasistatic (IQS) method. Numerical tests on a large light water reactor model indicate that the computational effort required with the IQS method can be reduced by a factor of 3 to 4 by using this new variational estimate of dynamic reactivity. With comparable computational effort, the accuracy of the standard IQS method, which uses the flux shape interpolation/recomputation procedure and a first-order estimate of static reactivity, can be improved by using a standard variational estimate without the flux shape interpolation/recomputation procedure, and it can be further improved by using the new variational estimate of dynamic reactivity.
