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Nuclear Installations Safety
Devoted specifically to the safety of nuclear installations and the health and safety of the public, this division seeks a better understanding of the role of safety in the design, construction and operation of nuclear installation facilities. The division also promotes engineering and scientific technology advancement associated with the safety of such facilities.
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Conference on Nuclear Training and Education: A Biennial International Forum (CONTE 2025)
February 3–6, 2025
Amelia Island, FL|Omni Amelia Island Resort
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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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A more open future for nuclear research
A growing number of institutional, national, and funder mandates are requiring researchers to make their published work immediately publicly accessible, through either open repositories or open access (OA) publications. In addition, both private and public funders are developing policies, such as those from the Office of Science and Technology Policy and the European Commission, that ask researchers to make publicly available at the time of publication as much of their underlying data and other materials as possible. These, combined with movement in the scientific community toward embracing open science principles (seen, for example, in the dramatic rise of preprint servers like arXiv), demonstrate a need for a different kind of publishing outlet.
Lester M. Waganer
Fusion Science and Technology | Volume 39 | Number 2 | March 2001 | Pages 458-461
Advanced Designs | doi.org/10.13182/FST01-A11963278
Articles are hosted by Taylor and Francis Online.
Two generic approaches for maintaining commercial fusion power plants are compared to determine the most desirable maintenance scheme and reactor design approach to consider for the next generation, advanced tokamak power plant, the ARIES-AT1. The scheduled and unscheduled maintenance times for the power core of fusion plants are extremely important as they directly determine the plant availability and, ultimately, the cost of electricity. The plant down time is determined by the time to access the failed or worn out part(s), the time to accomplish the replacement, and the time to verify the replacement.
The ARIES-AT power core2 is the design basis for this comparison. One possible maintenance approach is the in-situ removal of moderate-sized modules of individual first wall, blanket, and divertor elements from inside the tokamak power core. This approach potentially allows smaller and lower cost toroidal and poloidal field coils that tightly fit around the outer surface of the power core shield or vacuum vessel. A second approach uses larger toroidal and poloidal field coils that will allow much larger ports to extract a complete, intact sector module of the first wall, blanket, shield, and divertor elements.
The time to access and egress the power core components is largely determined by operations independent of the maintenance approach, such as reactor cool down, draining/filling fluids, unfastening/fastening doors, vacuum leak checks, etc. Replacement time of the core elements was found to significantly favor the modular sector approach because there are fewer and more accessible coolant and structural joints to unfasten and fasten. For the in-situ maintenance approach for ARIES-AT, there are more, but smaller, modules to handle than with the modular sector approach. Verification of the successful refurbishment is a distinct advantage for the modular sector approach because it can be operationally tested in a remote assembly area before being installed. Only a few main coolant connections will be verified within the power core region. For these reasons, the modular sector maintenance approach was adopted for the ARIES-AT conceptual design.
