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
Radiation Protection & Shielding
The Radiation Protection and Shielding Division is developing and promoting radiation protection and shielding aspects of nuclear science and technology — including interaction of nuclear radiation with materials and biological systems, instruments and techniques for the measurement of nuclear radiation fields, and radiation shield design and evaluation.
Meeting Spotlight
Conference on Nuclear Training and Education: A Biennial International Forum (CONTE 2025)
February 3–6, 2025
Amelia Island, FL|Omni Amelia Island Resort
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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Nuclear Science and Engineering
February 2025
Nuclear Technology
Fusion Science and Technology
Latest News
Resurrecting Three Mile Island
When Exelon Generation shut down Three Mile Island Unit 1 in September 2019, managers were so certain that the reactor would never run again that as soon as they could, they had workers drain the oil out of both the main transformer and a spare to eliminate the chance of leaks. The company was unable to find a buyer because of the transformers’ unusual design. “We couldn’t give them away,” said Trevor Orth, the plant manager. So they scrapped them.
Now they will pay $100 million for a replacement.
The turnaround at the reactor—now called the Crane Clean Energy Center—highlights two points: how smart Congress was to step in with help to prevent premature closures with the zero-emission nuclear power production credit of 0.3 cents per kilowatt-hour (only two years too late), and how expensive it is turning out to be to change course.
P. Deng, B. K. Jeon, H. Park, W. S. Yang
Nuclear Science and Engineering | Volume 193 | Number 12 | December 2019 | Pages 1310-1338
Technical Paper | doi.org/10.1080/00295639.2019.1621617
Articles are hosted by Taylor and Francis Online.
For accurate assessment of nuclear heating in fast reactors, a new coupled neutron and gamma heating calculation scheme has been developed based on VARIANT nodal transport solutions of neutron and gamma flux distributions. The MC2-3 code was extended to generate multigroup neutron and gamma cross sections and kinetic energy release in materials (KERMA) factors, and a utility program CURVE was developed to reconstruct detailed pin and duct wall powers from VARIANT output files. The improved heating calculation scheme has been verified against MCNP6 Monte Carlo reference solutions for the Advanced Burner Test Reactor (ABTR) and Experimental Breeder Reactor II (EBR-II) benchmark problems. Compared to the existing coupled heating calculation method based on DIF3D diffusion theory solutions, the new heating calculation scheme utilizes more accurate gamma cross sections and KERMA factors, accounts for the transport effects, and eliminates the approximations in the existing pin power reconstruction scheme. As a result, it produces more accurate assembly and pin power distributions. For both the ABTR and EBR-II problems, the maximum assembly power error was ~1% in fuel assemblies and ~2% in instrumented structure assemblies, and the maximum error in pin segment powers in an axial node of fuel assembly was ~4%. In the blankets of the EBR-II problem, the maximum error in pin segment powers was increased to ~8%, mainly due to the lower power level and the relatively large error in the nodal power of the VARIANT solution.
