ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
Explore membership for yourself or for your organization.
Conference 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!
Latest Magazine Issues
Jul 2025
Jan 2025
Latest Journal Issues
Nuclear Science and Engineering
September 2025
Nuclear Technology
August 2025
Fusion Science and Technology
Latest News
The Frisch-Peierls memorandum: A seminal document of nuclear history
The Manhattan Project is usually considered to have been initiated with Albert Einstein’s letter to President Franklin Roosevelt in October 1939. However, a lesser-known document that was just as impactful on wartime nuclear history was the so-called Frisch-Peierls memorandum. Prepared by two refugee physicists at the University of Birmingham in Britain in early 1940, this manuscript was the first technical description of nuclear weapons and their military, strategic, and ethical implications to reach high-level government officials on either side of the Atlantic. The memorandum triggered the initiation of the British wartime nuclear program, which later merged with the Manhattan Engineer District.
Seok-Hee Ryu, Kil-Sup Um, Jae-Il Lee
Nuclear Technology | Volume 189 | Number 2 | February 2015 | Pages 163-172
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT14-28
Articles are hosted by Taylor and Francis Online.
To evaluate the effect of thermal conductivity degradation for high-burnup fuel, a postulated control element assembly (CEA) ejection accident is assessed with the SPACE (Safety and Performance Analysis CodE) code. The SPACE code, which is currently under development as a safety analysis code for nuclear power plants, can predict thermal-hydraulic responses of the nuclear fuel and nuclear steam supply system during design basis accidents with two-fluid, three-field governing equations. Fuel performance behaviors during the CEA ejection accident using six fuel conductivity models including the burnup-independent reference conductivity model, the Lyons model, are investigated and compared with results of the reference model within the range from 0 to 30 GWd/tonne U. The Oak Ridge National Laboratory model predicts the highest peak fuel centerline temperature of 4531°F at 0 GWd/tonne U, and the modified Nuclear Fuels Institute model shows the uppermost value of 4796°F, which is 364°F higher than the reference model at 30 GWd/tonne U. It is also observed that the peak fuel centerline temperature increases linearly with fuel burnup and that the maximum increase rate of the peak centerline temperature per fuel burnup is ∼11.6°F per GWd/tonne U. For all thermal conductivity models, the maximum radial average fuel enthalpies are <230 cal/g, and the rise in radial average fuel enthalpy during the CEA ejection accident still remains within the pellet-cladding-mechanical-interaction failure criterion.
