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
Operations & Power
Members focus on the dissemination of knowledge and information in the area of power reactors with particular application to the production of electric power and process heat. The division sponsors meetings on the coverage of applied nuclear science and engineering as related to power plants, non-power reactors, and other nuclear facilities. It encourages and assists with the dissemination of knowledge pertinent to the safe and efficient operation of nuclear facilities through professional staff development, information exchange, and supporting the generation of viable solutions to current issues.
Meeting Spotlight
2022 ANS Annual Meeting
June 12–16, 2022
Anaheim, CA|Anaheim 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
May 2022
Jan 2022
Latest Journal Issues
Nuclear Science and Engineering
June 2022
Nuclear Technology
July 2022
Fusion Science and Technology
Latest News
Finding fusion’s place
Fusion energy is attracting significant interest from governments and private capital markets. The deployment of fusion energy on a timeline that will affect climate change and offer another tool for energy security will require support from stakeholders, regulators, and policymakers around the world. Without broad support, fusion may fail to reach its potential as a “game-changing” technology to make a meaningful difference in addressing the twin challenges of climate change and geopolitical energy security.
The process of developing the necessary policy and regulatory support is already underway around the world. Leaders in the United States, the United Kingdom, the European Union, China, and elsewhere are engaging with the key issues and will lead the way in setting the foundation for a global fusion industry.
B. Zhao, S. A. Musa, S. I. Abdel-Khalik, M. Yoda
Fusion Science and Technology | Volume 72 | Number 3 | October 2017 | Pages 300-305
Technical Paper | dx.doi.org/10.1080/15361055.2017.1333828
Articles are hosted by Taylor and Francis Online.
The leading candidate for the DEMO divertor is the helium-cooled modular divertor with multiple jets (HEMJ) design, which is to date the only design that has been experimentally shown to accommodate incident steady-state heat fluxes greater than 10 MW/m2. In the HEMJ, the divertor target plates are cooled by 25 jets of different diameters that impinge upon a curved tungsten (W)-alloy surface brazed to a hexagonal W tile. Given the difficulties in manufacturing such a complicated geometry in W and W-alloys, numerical simulations were performed to determine if simplified versions of the HEMJ design could provide similar thermal-hydraulic performance. Parametric studies were performed at fully prototypical conditions using one-way coupled thermo-mechanical and fluid dynamics simulations in ANSYS® Workbench® to determine the effect of varying the jet-to-cooled surface distance, the number, diameter, and spacing of the jet holes (the jets were all assumed to have the same diameter), and the curvature of the cooled surface on the thermal-hydraulic performance. The results for the evaluated 75 different jet array configurations suggest that similar and even superior thermal-hydraulic performance can be provided by several designs. These HEMJ variants with fewer jets and larger holes may reduce fabrication costs and improve reliability. For example, the simulations suggest that a configuration involving flat surfaces with six holes surrounding one central hole, all with a diameter of 1.18 mm at a jet-to-cooled surface distance of 1.25 mm provides a 6.6% higher average heat transfer coefficient (HTC) at a 4.8% lower pressure drop when compared with the HEMJ. The maximum temperature of the outer shell and cooled surface stress are also lower for this design. In all cases, the simulations also suggest that the jet-to-cooled surface distance decreases by approximately 0.2 mm when the temperature increases from ambient to prototypical conditions due to differential thermal expansion of the jets cartridge and the W-alloy pressure boundary.
