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
2026 Annual Conference
May 31–June 3, 2026
Denver, CO|Sheraton Denver
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
Dec 2025
Jul 2025
Latest Journal Issues
Nuclear Science and Engineering
December 2025
Nuclear Technology
Fusion Science and Technology
November 2025
Latest News
Perpetual Atomics, QSA Global produce Am fuel for nuclear space power
U.K.-based Perpetual Atomics and U.S.-based QSA Global claim to have achieved a major step forward in processing americium dioxide to fuel radioisotope power systems used in space missions. Using an industrially scalable process, the companies said they have turned americium into stable, large-scale ceramic pellets that can be directly integrated into sealed sources for radioisotope power systems, including radioisotope heater units (RHUs) and radioisotope thermoelectric generators (RTGs).
M. Ishii, W. L. Chen, M. A. Grolmes
Nuclear Science and Engineering | Volume 60 | Number 4 | August 1976 | Pages 435-451
Technical Paper | doi.org/10.13182/NSE76-3
Articles are hosted by Taylor and Francis Online.
The motion and location of the molten clad during an unprotected loss-of-flow accident in liquid-metal fast breeder reactors are very important because of their effect on the reactivity and the subsequent fuel motion. The present study analyzes the clad relocation problem based on a single-channel film flow model and a simple thermal transient model for fuel pins. The motion of molten clad induced by sodium vapor streaming undergoes initial rapid upward acceleration, slowing down, flow reversal, and eventual slumping down into liquid sodium at the lower end of the heated section. A possibility for freezing of the molten clad at the unheated upper plenum region as well as bottom freezing and blockage formation were also included in the analysis. A sample calculation has been made for the case of R-series 7-pin tests in the Transient Reactor Test Facility. The agreement of the overall physical behavior of the clad motion with the post-test observations is quite satisfactory.