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Young Members Group
The Young Members Group works to encourage and enable all young professional members to be actively involved in the efforts and endeavors of the Society at all levels (Professional Divisions, ANS Governance, Local Sections, etc.) as they transition from the role of a student to the role of a professional. It sponsors non-technical workshops and meetings that provide professional development and networking opportunities for young professionals, collaborates with other Divisions and Groups in developing technical and non-technical content for topical and national meetings, encourages its members to participate in the activities of the Groups and Divisions that are closely related to their professional interests as well as in their local sections, introduces young members to the rules and governance structure of the Society, and nominates young professionals for awards and leadership opportunities available to members.
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.
R. Muralidharan, V. K. Chexal
Nuclear Technology | Volume 78 | Number 1 | July 1987 | Pages 13-23
Technical Paper | Nuclear Safety | doi.org/10.13182/NT87-A34004
Articles are hosted by Taylor and Francis Online.
The emergency core cooling systems (ECCSs) at a reactor site have a dual power source for their assured operation if and when needed. The normal power source is the off-site ac power. In the unlikely event of loss of all off-site power, emergency diesel generators (DGs) are the backup ac source. Thus, there is an incentive to ensure that the reliability of DGs at operating plants is maintained at an acceptable level. A potential contributor to observed diesel degradation is the fast start and loading interval (∼10 s) demanded of the emergency DGs. Such fast start intervals result from the performance required of the ECCS to meet the U.S. Nuclear Regulatory Commission (NRC) acceptance criteria for a hypothetical large-break loss-of-coolant accident (LOCA) (design basis accident) concurrent with a loss of off-site power. The guidelines established by the NRC for the ECCS performance evaluation, which are stated in Appendix K of 10CFR50, have several built-in arbitrary conservatisms. Recently, the NRC outlined in SECY-83-472 a new approach for performing ECCS analysis and has given approval to General Electric to use this new approach in their SAFER/GESTR LOCA analysis computer code. The sensitivity of peak cladding temperature (PCT) is determined using the new realistic LOCA analysis approach for various DG start durations. A quantitative assessment of the various diesel start durations using NRC licensing assumptions was made to determine the impact on the PCT. The results for a boiling water reactor (BWR/6) show that when using licensing assumptions and the SAFER/GESTR code, the PCT that is determined during a design basis LOCA for the present 10-s DG start criteria is ∼593°C. This is far below the prescribed limit of 1204.4°C. The results also show that the PCT varies only a small amount with diesel start times of 10 to 30 s. Thus, the diesel start time for the class of reactors analyzed in this study could be changed from 10 to 30 s without the loss of any LOCA safety margin. The results further show that for an 871.1°C PCT, which is the current NRC-approved SAFER application PCT limit, the DG start time can be 70 s (compared to the present specified 10 s). The DG start time could be increased to 118 s when and if, in the future, the SAFER code is qualified to a PCT limit of 1204.4°C for licensing calculations. This work is of interest to nuclear utilities as a means of increasing operational flexibility and to help improve diesel reliability.
