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
2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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
Sep 2025
Jan 2025
Latest Journal Issues
Nuclear Science and Engineering
October 2025
Nuclear Technology
September 2025
Fusion Science and Technology
Latest News
Type One Energy, TVA ink LOI in development of fusion power in Tennessee
The Tennessee Valley Authority has issued a letter of intent to fusion energy start-up Type One Energy regarding the utility’s interest in the potential deployment of Type One Energy’s fusion power plant technology at TVA’s former Bull Run fossil plant site once it is commercially ready.
David A. Petti, James P. Adams, James L. Anderson, Richard R. Hobbins
Nuclear Technology | Volume 87 | Number 1 | August 1989 | Pages 243-263
Technical Paper | TMI-2: Materials Behavior / Nuclear Safety | doi.org/10.13182/NT89-A27652
Articles are hosted by Taylor and Francis Online.
An analysis of fission product release during the Three Mile Island Unit 2 (TMI-2) accident has been performed to provide an understanding of fission product behavior that is consistent with both the best-estimate accident scenario and fission product results from the sample acquisition and examination efforts. “Firstprinciples” fission product release models are used to describe release from intact, disrupted, and molten fuel during the various phases of the TMI-2 accident. Extensive gaseous and volatile fission product release is calculated to have occurred, with local regions of the core experiencing up to 100% release. Diffusion is calculated to have dominated release during the initial core heatup, while bubble coalescence and rise dominated release from the large consolidated region of molten material. The calculations are generally consistent with fission product retention data from upper and lower plenum debris bed samples. An exception to this is the small retention of cesium in the lower plenum samples, suggesting that cesium may have been in a low-volatile chemical form. The small release fractions measured for the less volatile fission product oxides (SrO, Eu2O3, and Ce2O3) are calculated to have resulted from the low partial pressures of these species in the melt coupled with the low surface-to-volume ratio of the consolidated melt region. Metallic species (ruthenium and antimony) are thought to be associated with metallic core structural material debris.