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.
Division Spotlight
Fuel Cycle & Waste Management
Devoted to all aspects of the nuclear fuel cycle including waste management, worldwide. Division specific areas of interest and involvement include uranium conversion and enrichment; fuel fabrication, management (in-core and ex-core) and recycle; transportation; safeguards; high-level, low-level and mixed waste management and disposal; public policy and program management; decontamination and decommissioning environmental restoration; and excess weapons materials disposition.
Meeting Spotlight
International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver Downtown
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
Apr 2025
Jan 2025
Latest Journal Issues
Nuclear Science and Engineering
June 2025
Nuclear Technology
Fusion Science and Technology
May 2025
Latest News
Argonne’s METL gears up to test more sodium fast reactor components
Argonne National Laboratory has successfully swapped out an aging cold trap in the sodium test loop called METL (Mechanisms Engineering Test Loop), the Department of Energy announced April 23. The upgrade is the first of its kind in the United States in more than 30 years, according to the DOE, and will help test components and operations for the sodium-cooled fast reactors being developed now.
Michitsugu Mori
Nuclear Technology | Volume 128 | Number 2 | November 1999 | Pages 205-215
Technical Paper | RETRAN | doi.org/10.13182/NT99-A3025
Articles are hosted by Taylor and Francis Online.
The advanced boiling water reactor (ABWR) has ten reactor-internal pumps peripherally mounted on the bottom of a reactor vessel. Analytical simulation of reactor-internal pumps unique to the ABWR requires new modeling because of the difference in core flow characteristics between the reactor-internal pumps and the two external-recirculation pumps of the primary outer loops with the jet pumps in a current boiling water reactor. Efforts in this work focused on modeling and simulation of reactor-internal pumps and core flow of the ABWR, using the RETRAN-3D code, the computer program for transient thermal-hydraulic analysis of a complex fluid flow system, without multidimensional kinetics. Included are modeling of the core and reactor pressure vessel with ten reactor-internal pumps, and simulation of the events of reactor-internal-pumps trip during the startup-phase tests, which are unable to be done in the simulation of a current BWR. Sensitivity analyses on the recirculation flow control and the slip model were also performed. The predictions by the RETRAN-3D code successfully tracked the measured data of reactor-internal-pump trip during the startup-phase test. The present analytical simulations could demonstrate the validation of the RETRAN-3D code applicable to the ABWR with the pump model of reactor-internal pumps in the program.