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
Robotics & Remote Systems
The Mission of the Robotics and Remote Systems Division is to promote the development and application of immersive simulation, robotics, and remote systems for hazardous environments for the purpose of reducing hazardous exposure to individuals, reducing environmental hazards and reducing the cost of performing work.
Meeting Spotlight
ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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
May 2025
Nuclear Technology
April 2025
Fusion Science and Technology
Latest News
Norway’s Halden reactor takes first step toward decommissioning
The government of Norway has granted the transfer of the Halden research reactor from the Institute for Energy Technology (IFE) to the state agency Norwegian Nuclear Decommissioning (NND). The 25-MWt Halden boiling water reactor operated from 1958 to 2018 and was used in the research of nuclear fuel, reactor internals, plant procedures and monitoring, and human factors.
Nicholas R. Brown, Seungmin Oh, Shripad T. Revankar, Cheikhou Kane, Salvador Rodriguez, Randall Cole, Jr., Randall Gauntt
Nuclear Technology | Volume 166 | Number 1 | April 2009 | Pages 43-55
Technical Paper | Special Issue on Nuclear Hydrogen Production, Control, and Management | doi.org/10.13182/NT09-A6967
Articles are hosted by Taylor and Francis Online.
This paper presents a transient control volume modeling scheme for both the sulfur-iodine (SI) and Westinghouse hybrid sulfur (HyS) thermochemical cycles. These cycles are very important candidates for the large-scale production of hydrogen in the 21st century. In this study, transient control volume models of the SI and HyS cycles are presented, along with a methodology for coupling these models to codes that describe the transient behavior of a high-temperature nuclear reactor. The transient SI and HyS cycle models presented here are based on a previous model with a significant improvement, namely, pressure variation capability in the chemical reaction chambers. This pressure variation capability is obtained using the ideal gas law, which is differentiated with respect to time. The HyS model is based on a time-dependent application of the Nernst equation. Investigation of the new pressure assumption yields a peak pressure rate of change of 5.877 kPa/s for a temperature-driven transient test matrix and 2.993 kPa/s for a mass flow rate-driven transient test matrix. These high rates of pressure change suggest that an accurate model of the SI and/or HyS cycle must include some method of accounting for pressure variation. The HyS model suggests that the hydrogen production rate is directly proportional to the SO2 production rate.