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Division Spotlight
Nuclear Installations Safety
Devoted specifically to the safety of nuclear installations and the health and safety of the public, this division seeks a better understanding of the role of safety in the design, construction and operation of nuclear installation facilities. The division also promotes engineering and scientific technology advancement associated with the safety of such facilities.
Meeting 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
NRC’s David Wright visits the Hill and more NRC news
Wright
The Nuclear Regulatory Commission is in the spotlight today for three very different reasons. First, NRC Chair David Wright was on Capitol Hill yesterday for his renomination hearing in front of the Senate’s Environment and Public Works Committee. Second, the NRC released its updated milestone schedules according to the Nuclear Energy Innovation and Modernization Act (NEIMA) and the executive orders signed by President Trump last month; and third, as reported by Reuters on Tuesday, 28 former NRC officials have condemned the dismissal of Commissioner Hanson earlier this month.
Renomination: EPW Committee chair Sen. Shelley Moore Capito (R., W.Va.) opened the hearing with a statement praising Wright’s experience and emphasized the urgency of stable leadership at the NRC.
“China is executing a rapid build-out of its nuclear industry,” Capito said. “The demand for clean, baseload power is skyrocketing as we position America to win the AI race.”
Tomomi Uchiyama
Nuclear Science and Engineering | Volume 134 | Number 3 | March 2000 | Pages 281-292
Technical Paper | doi.org/10.13182/NSE00-A2116
Articles are hosted by Taylor and Francis Online.
The air-water two-phase flow across a staggered tube bundle at a pitch-to-diameter ratio of 1.4 is analyzed by an incompressible two-fluid model using the upstream finite element method proposed in a prior study. The Reynolds number, based on the tube diameter and the volumetric velocity of the liquid phase at the tube gap, is 41 000, and the volumetric fraction of the gas phase upstream of the bundle g0 ranges from 0 to 0.15. The calculated flows exhibit unsteady and complicated behavior irrespective of g0. The change in the drag coefficient of a tube in the bundle due to g0 agrees with the experimental result. The distribution of the volumetric fraction of the gas phase around the tube is also in good agreement with the measurement trend. These results indicate that the finite element method is usefully applicable to the two-phase-flow analysis in staggered tube bundles. It is also clarified that the unsteady flows are attributable to the occurrence and movement of vortices of both phases around the tubes.
