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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
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.
M. T. Friend, R. F. Wright, R. Hundal, L. E. Hochreiter, M. Ogrins
Nuclear Technology | Volume 122 | Number 1 | April 1998 | Pages 19-42
Technical Paper | Reactor Safety | doi.org/10.13182/NT98-A2848
Articles are hosted by Taylor and Francis Online.
As part of the AP600 design certification program, a series of component separate effects tests and two integral systems tests of the nuclear steam supply system were performed. These tests were designed to provide data necessary to validate Westinghouse safety analysis codes for AP600 applications. In addition, the tests have provided the opportunity to investigate the thermal-hydraulic phenomena that are expected to be important in AP600 transients. One series of integral systems tests was undertaken on the SPES-2 facility in Italy, a full-height, full-pressure, 1/395th-power and -volume scale simulation of the AP600 nuclear steam supply system and passive safety features. A series of thirteen design-basis events were simulated at SPES-2 to obtain data for verification and validation of the computer models used for the safety analysis of the AP600. The modeled initiating events included a series of small-break loss-of-coolant accidents (SBLOCAs), single steam generator tube ruptures, and a main steam-line break.The results of the analyses of the SPES-2 test data, performed to investigate the performance of the safety-related systems are reported. These analyses were also designed to demonstrate, through mass and energy inventory calculations, mass and energy balances, and event timing analyses, the applicability of the SPES-2 tests for computer model verification and validation. The key thermal-hydraulic phenomena simulated in the SPES-2 tests and the performance and interactions of the passive safety-related systems that can be investigated through the SPES-2 facility are emphasized. The latter includes the impact of accumulator nitrogen and nonsafety-related system actuation on the passive safety-related system performance.It is concluded that the key thermal-hydraulic phenomena that characterize the SBLOCA and non-LOCA transients have been successfully simulated in the SPES-2 facility, and the test results can be used to validate the AP600 safety analysis computer codes. The SPES-2 tests demonstrate that the AP600 passive safety-related systems successfully combine to provide a continuous removal of core decay heat. The SPES-2 tests also showed no adverse interactions between the passive safety-related system components or with the nonsafety-related systems. In particular, it was found that the effect of noncondensable nitrogen on passive safety-related system performance was negligible.