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
Nov 2025
Jul 2025
Latest Journal Issues
Nuclear Science and Engineering
December 2025
Nuclear Technology
Fusion Science and Technology
November 2025
Latest News
X-energy raises $700M in latest funding round
Advanced reactor developer X-energy has announced that it has closed an oversubscribed Series D financing round of approximately $700 million. The funding proceeds are expected to be used to help continue the expansion of its supply chain and the commercial pipeline for its Xe-100 advanced small modular reactor and TRISO-X fuel, according the company.
Rui Hu, Mujid S. Kazimi
Nuclear Technology | Volume 177 | Number 1 | January 2012 | Pages 8-28
Technical Paper | Fission Reactors | doi.org/10.13182/NT12-A13324
Articles are hosted by Taylor and Francis Online.
The TRACE/PARCS code was applied in this work to examine the validity of the coupled three-dimensional thermal-hydraulics and neutronics system analysis codes for boiling water reactor stability analysis. The evaluation was performed against the Ringhals-1 stability tests and compared with the frequency domain analysis using the code STAB. A comprehensive assessment of modeling choices for the TRACE stability analysis has been made, including effects of time-space discretization and numerical schemes, thermal-hydraulics channel grouping, neutronics modeling, and control system modeling. It was found that with careful control of numerical diffusion, the predictions from TRACE agree reasonably well with the Ringhals-1 test results and the predictions from STAB. The benchmark results of both codes against the Ringhals stability test are found to be at the same level of accuracy. The biases for the predicted global decay ratio are [approximately]0.07 in TRACE results and -0.04 in STAB results. However, the standard deviations of their decay ratios are both large, [approximately]0.1, indicating large uncertainties in both analyses. The uncertainties in both modeling approaches are identified. Although the TRACE code uses more sophisticated neutronics and thermal-hydraulics models, the modeling uncertainty is not less than that of the STAB code.