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Division Spotlight
Accelerator Applications
The division was organized to promote the advancement of knowledge of the use of particle accelerator technologies for nuclear and other applications. It focuses on production of neutrons and other particles, utilization of these particles for scientific or industrial purposes, such as the production or destruction of radionuclides significant to energy, medicine, defense or other endeavors, as well as imaging and diagnostics.
Meeting Spotlight
2025 ANS Annual Conference
June 15–18, 2025
Chicago, IL|Chicago Marriott 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!
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Smarter waste strategies: Helping deliver on the promise of advanced nuclear
At COP28, held in Dubai in 2023, a clear consensus emerged: Nuclear energy must be a cornerstone of the global clean energy transition. With electricity demand projected to soar as we decarbonize not just power but also industry, transport, and heat, the case for new nuclear is compelling. More than 20 countries committed to tripling global nuclear capacity by 2050. In the United States alone, the Department of Energy forecasts that the country’s current nuclear capacity could more than triple, adding 200 GW of new nuclear to the existing 95 GW by mid-century.
Yassin A. Hassan, Changwoo Kang
Nuclear Technology | Volume 180 | Number 2 | November 2012 | Pages 159-173
Technical Paper | Fission Reactors | doi.org/10.13182/NT12-A14631
Articles are hosted by Taylor and Francis Online.
Pressure drops over a packed bed of a pebble bed reactor were investigated. Measurements of porosity and pressure drop over the bed were carried out in a cylindrical packed-bed facility. Air and water were used for the working fluids. There are several parameters influencing the pressure drop in packed beds. One of the most important factors is the wall effect. The inhomogeneous porosity distribution in the bed and the additional wetted surface introduced by the wall cause variation of the pressure drop. The importance of wall effects and porosity can be explained by using different bed-to-particle-diameter ratios. Four different bed-to-particle-diameter ratios were used in these experiments (D/dp = 19, 9.5, 6.33, and 3.65). A comparison is made between the predictions by a number of empirical correlations including the Ergun equation (1952) and that of the Nuclear Safety Standards Commission (KTA) in the literature. Analysis of the data indicates the importance of the bed-to-particle-size ratio on the pressure drop. The comparison between the present and the existing correlations showed that the pressure drop of large bed-to-particle-diameter ratios (D/dp = 19, 9.5, and 6.33) matched very well with the original KTA correlation. However, the published correlations cannot be expected to predict accurate pressure drop for certain conditions, especially for pebble beds with D/dp 5. An improved correlation was obtained for a small bed-to-particle-diameter ratio by fitting the coefficients of that equation to experimental databases.
