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 ANS Annual Conference
May 31–June 3, 2026
Denver, CO|Sheraton Denver
Latest Magazine Issues
Mar 2026
Jul 2025
Latest Journal Issues
Nuclear Science and Engineering
March 2026
Nuclear Technology
February 2026
Fusion Science and Technology
April 2026
Latest News
NRC approves TerraPower construction permit
Today, the Nuclear Regulatory Commission announced that it has approved TerraPower’s construction permit application for Kemmerer Unit 1, the company’s first deployment of Natrium, its flagship sodium fast reactor.
This approval is a significant milestone on three fronts. For TerraPower, it represents another step forward in demonstrating its technology. For the Department of Energy, it reflects progress (despite delays) for the Advanced Reactor Demonstration Program (ARDP). For the NRC, it is the first approval granted to a commercial reactor in nearly a decade—and the first approval of a commercial non–light water reactor in more than 40 years.
S. Mostafa Ghiaasiaan, A. Telal Wassel, Murthy S. Divakaruni
Nuclear Technology | Volume 81 | Number 1 | April 1988 | Pages 13-27
Technical Paper | Fission Reactor | doi.org/10.13182/NT88-A34075
Articles are hosted by Taylor and Francis Online.
An engineering model was developed to simulate the thermal-hydraulic phenomena in pressurized water reactor cores during bottom reflooding. The model couples the fluid thermal hydraulics and radial heat transfer in the fuel rods. The system dynamics were formulated in terms of a set of ordinary differential equations, which were integrated using the Gear integration package. A dynamic nodal scheme, which moves with the quench-front location, was utilized to predict the fuel rod temperatures. Model predictions and comparisons with full-scale experiments are provided, and show good agreement with the FLECHT-SEASET and Slab Core Test Facility data. The proposed methodology was found to be computationally fast when compared with previous approaches, and can be readily integrated with other modules to simulate the complete reactor coolant system.