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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
Utility Working Conference and Vendor Technology Expo (UWC 2024)
August 4–7, 2024
Marco Island, FL|JW Marriott Marco Island
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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Nuclear Science and Engineering
August 2024
Nuclear Technology
Fusion Science and Technology
Latest News
Virginia utility considers SMRs
Dominion Energy Virginia has issued a request for proposals from leading nuclear companies to study the feasibility of putting a small modular reactor at its North Anna nuclear power plant.
While the utility says it is not a commitment to build an SMR at the site, the RFP is “an important first step in evaluating the technology and the North Anna site to support Dominion Energy customers’ future energy needs consistent with the company’s most recent Integrated Resource Plan.”
Yoshiro Asahi, Ichiro Sugawara, Toshiki Kobayashi
Nuclear Technology | Volume 91 | Number 1 | July 1990 | Pages 28-50
Technical Paper | Safety of Next Generation Power Reactor / Fission Reactor | doi.org/10.13182/NT90-A34439
Articles are hosted by Taylor and Francis Online.
The Integrated Reactor with Inherent Safety (IRIS) has been designed with a primary objective of ensuring fuel integrity by passive means only. The steam generator is a once-through helical coil type. The steel reactor pressure vessel is submerged in an outer pool contained in a prestressed concrete containment vessel. Thus, the coolant in the reactor containment vessel has a very low average specific enthalpy (243 kJ/kg), while its heat capacity is very large (42 GJ/°C). The primary flow path, which has a double syphon structure with the main coolant pumps located at the outlet of the steam generator, is formed by concentric annuli. The various components required for steady-state plant operation are driven by a turbine or by on-site power so that they can be automatically shut down. Due to these passive features, not only are various systems simplified or eliminated, but constraints on the plant layout are also reduced. Balance of mass, heat, and pressure are examined by computer calculations, and various geometric and thermal-hydraulic parameters are chosen. The reactor control logic is designed so that the IRIS can cope with a large loss of load. Safety analyses confirm that the reactor passively shuts itself down in accidents; for example, in a loss-of-coolant accident due to a break in the outer pool, the borated outer pool water is passively injected into the reactor pressure vessel through the break. A negative void coefficient is especially important in the IRIS since it does not have control rods. The atmosphere is used by heat pipes as the ultimate heat sink for decay heat removal; thus, the walkaway period is very long.