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Division Spotlight
Robotics & Remote Systems
The Mission of the Robotics and Remote Systems Division is to promote the development and application of immersive simulation, robotics, and remote systems for hazardous environments for the purpose of reducing hazardous exposure to individuals, reducing environmental hazards and reducing the cost of performing work.
Meeting Spotlight
2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
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
Nuclear new build procurement considerations
It may seem counterintuitive, but the best time to enhance the ability to support operations and maintenance for a new plant is before construction starts. This is one of many lessons learned by the currently operating nuclear fleet. As construction and startup of many nuclear facilities was completed, it quickly became evident that the ability to efficiently support operations and maintenance was limited. Most of the information necessary to establish and manage procurement of spare and replacement items, maintenance, and configuration of the facilities was unavailable and had to be gathered on a case-by-case, “on-demand” basis. Absence of necessary information and the associated challenges resulted in the need for staff augmentation and multiyear-long projects to develop equipment bills of material and maintenance programs and to perform technical evaluations for the huge quantities of spare and replacement items being requested.
Delgersaikhan Tuya, Toru Obara
Nuclear Science and Engineering | Volume 193 | Number 5 | May 2019 | Pages 481-494
Technical Paper | doi.org/10.1080/00295639.2018.1540209
Articles are hosted by Taylor and Francis Online.
A multiregion integral kinetic (MIK) code based on the integral kinetic model and a Monte Carlo neutron transport method has been developed with a new time-dependent feedback modeling capability. The current MIK code is applicable to the supercritical power transient following reactivity insertion in a fissile system of arbitrary geometry and composition, taking its feedback mechanisms into account. The new time-dependent feedback modeling capability allows a more direct and accurate treatment of complicated and nonlinear feedback mechanisms in a given system. The purpose of this study is to verify the MIK code and its time-dependent feedback modeling capability through various supercritical transient experiments conducted at the Godiva, TRACY, and SILENE facilities. Specifically, four supercritical experiments were selected and simulated using the MIK code. The various complicated feedback mechanisms—thermal expansion in Godiva, and Doppler broadening, thermal expansion, and radiolytic gas creation in TRACY and SILENE—provide a good benchmark for verifying the MIK code and its time-dependent feedback model. The obtained results show generally good, albeit occasionally poor, agreement with experimental results depending on the specific experiment. When the reasons for the poor agreement are considered, however, it may be concluded that the simulated results show promising agreement with the experiments, verifying the MIK code and its time-dependent feedback modeling capability.