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Aerospace Nuclear Science & Technology
Organized to promote the advancement of knowledge in the use of nuclear science and technologies in the aerospace application. Specialized nuclear-based technologies and applications are needed to advance the state-of-the-art in aerospace design, engineering and operations to explore planetary bodies in our solar system and beyond, plus enhance the safety of air travel, especially high speed air travel. Areas of interest will include but are not limited to the creation of nuclear-based power and propulsion systems, multifunctional materials to protect humans and electronic components from atmospheric, space, and nuclear power system radiation, human factor strategies for the safety and reliable operation of nuclear power and propulsion plants by non-specialized personnel and more.
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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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Fusion Science and Technology
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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.
D.K. Murdoch, F. Olezza, J-L. Mazel
Fusion Science and Technology | Volume 21 | Number 2 | March 1992 | Pages 966-970
Material; Storage and Processing | doi.org/10.13182/FST92-A29876
Articles are hosted by Taylor and Francis Online.
Large diameter (up to approx. 2 m) tritium compatible vacuum valves will be required for a broad range of applications around the NET/ITER torus. This paper focuses on the development steps and current design status of the valves located immediately upstream of the torus primary vacuum pumps. The number (24) and size (1500 mm nominal diameter) of these valves has been established in studies of the required particle exhaust rate from the torus and the conductance of the divertor duct and manifold system. The three principal functions are to isolate the torus during maintenance, to prevent back-streaming during regeneration of compound cryopumps, and to provide fast closure following accident or upset conditions. The design input parameters are tabulated in the paper. Initial engineering studies indicate that a gate valve is the preferred configuration to achieve low conductance losses and a design compatible with the confined space available. In order to meet the specified internal leak tightness (10−4 Pa.m3. s−1) in the potentially dust-laden environment, an elastomeric sealing material is recommended. This will keep the sealing forces and therefore the overall weight and dimensions of the valve within acceptable limits. Because of the arduous operating environment (dust, tritium, neutron activation and high operating frequency) provision will be made for change-out of the valve seals as a routine maintenance activity. A valve design in which the bonnet, stem and valve disc (along with the elastomer seal rings) can be removed from the valve body by a remotely operated manipulator and transferred to a centralized hot cell location for refurbishment has therefore been specified. Development of the valve includes both engineering studies and laboratory test work, and these are described in the paper. A prototype valve will be available in 1995–96 for incorporation into an integrated vacuum system test loop.
