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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
2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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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Latest News
Can hydrogen be the transportation fuel in an otherwise nuclear economy?
Let’s face it: The global economy should be powered primarily by nuclear power. And it probably will by the end of this century, with a still-significant assist from renewables and hydro. Once nuclear systems are dominant, the costs come down to where gas is now; and when carbon emissions are reduced to a small portion of their present state, it will become obvious that most other sources are only good in niche settings. I mean, why use small modular reactors to load-follow when they can just produce that power instead of buffering it?
Tai-Hung Wu, De-Cheng Chen
Nuclear Technology | Volume 205 | Number 6 | June 2019 | Pages 867-880
Technical Note | doi.org/10.1080/00295450.2018.1533320
Articles are hosted by Taylor and Francis Online.
Station blackout (SBO) sequences for a Westinghouse-designed three-loop pressurized water reactor (PWR) with large dry containment are investigated. Recovery of alternating-current power is considered under two separate headings in event trees of loss of off-site power: recovery of the off-site power and recovery of the emergency diesel generators (EDGs) or diesel generator 5. A reactor coolant pump seal leakage model under SBO conditions for a Westinghouse PWR with high-temperature O-rings is used. Seal failure mechanisms, including popping open, binding, and O-ring extrusion, are considered. Success criteria are established based on the results of thermal-hydraulic calculations via the MELCOR and/or RELAP-5 codes. Furthermore, the WinNUPRA software package is used for sequence quantification.
Three primary models are addressed: Basic, WOG2000, and Ultimate Response Guideline (URG). The core damage frequency (CDF) of SBO sequences for the Basic model is found to be very optimistic and underestimated. The improvement on CDF by introducing the URG model is found to be dependent primarily on the reliability of plant operators in performing the procedure URG under SBO situations.
Two sensitivity analyses on the passive shutdown seal (PSDS) are performed: WOG2000 (PSDS) and URG (PSDS). The low-failure-probability PSDS results in a >94% improvement in CDF due to SBO since the CDF contribution from long-term SBO sequences becomes negligible. Furthermore, the URG strategies are shown to have a significant impact on the reduction of CDF since seal leakage is no longer a concern in the presence of the PSDS.
The way that power recovered is distinguished from off-site power or on-site EDGs and the way that SBO CDF is assessed make the present study more realistic than general SBO models.
A key analysis of the confidence bands of the SBO CDF with the aid of the uncertainty measure is also performed to observe the induced effects by the probabilistic seal failure modes and PSDS.