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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.
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2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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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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Former Exelon CEO Chris Crane remembered for “transformational milestones”
Crane
Exelon announced that Chris Crane, the company’s former chief executive, passed away on Saturday in Chicago at the age of 65.
Crane served as the company’s president and CEO from 2012 until his retirement in December 2022. During his tenure, he steered the energy company through several transformational milestones, including the successful mergers with Constellation Energy in 2012 and Pepco Holdings in 2016, creating the largest utility business by customer count in the United States.
In 2022, with the spin-off of Constellation as the generation and retail side of energy business (with the largest U.S. nuclear fleet), Crane led the creation of a stand-alone transmission and delivery energy company.
T. V. Dury, M. T. Dhotre
Nuclear Science and Engineering | Volume 165 | Number 1 | May 2010 | Pages 101-116
Technical Paper | doi.org/10.13182/NSE08-90
Articles are hosted by Taylor and Francis Online.
Current designs of pressurized water reactors (PWRs) employ a boric acid solution in the primary cooling water to control core reactivity during operation and shutdown. However, situations could theoretically occur in which diluted borated water is present in the primary circuit. Scale experiments have been performed for a single-pump start-up, with subsequent computational fluid dynamics (CFD) simulation, to examine the accuracy with which the concentration distribution of diluted borated water entering a reactor core can be predicted. It was concluded that higher-order advection schemes must be used to obtain sufficient resolution of the velocity field and capture the larger-scale effects of the flow but that each turbulence model produces a different core-inlet boron concentration development and distribution. Though it was not the most sophisticated available, the two-equation RNG k- turbulence model produced the closest agreement with experiment. However, mesh independence of the computational results was not achieved. As a sequel to this scaled CFD study, a simulation was carried out of a full-size three-loop Siemens-type PWR featuring a perforated cylindrical flow baffle in the lower plenum. Results again showed different characteristics in time and space, depending on the turbulence model used. Comparative assessment of the results obtained with the code CFX-5 showed that correct geometrical modeling of a perforated flow baffle in the lower plenum is essential, as a porous medium representation of the baffle can lead to serious underprediction of mixing. This occurred particularly with the RNG model but also using more sophisticated turbulence models. Further refinement of the mesh is now necessary to achieve mesh independence of the results. This requires access to a massively parallel computer system.