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Reactor Physics
The division's objectives are to promote the advancement of knowledge and understanding of the fundamental physical phenomena characterizing nuclear reactors and other nuclear systems. The division encourages research and disseminates information through meetings and publications. Areas of technical interest include nuclear data, particle interactions and transport, reactor and nuclear systems analysis, methods, design, validation and operating experience and standards. The Wigner Award heads the awards program.
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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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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.
Yu-Huai Shih, Te-Chuan Wang
Nuclear Technology | Volume 193 | Number 2 | February 2016 | Pages 247-258
Technical Paper | doi.org/10.13182/NT14-118
Articles are hosted by Taylor and Francis Online.
When an accident occurs, operators in nuclear power plants (NPPs) must follow emergency operating procedures (EOPs) or severe accident management guidelines (SAMGs). However, EOPs and SAMGs are symptom-based procedures and guidelines to cope with severe transients and accidents. Operators depend on real-time operating parameters of NPPs to perform each action in EOPs or SAMGs. When a beyond-design-basis accident like the Fukushima Daiichi accident of 2011 occurs, EOPs or SAMGs cannot be performed effectively without adequate information. One lesson learned from the Fukushima accident is that such a situation requires advance preparation regarding the key indicators, the water supply, reactor pressure vessel (RPV) depressurization, and containment venting strategies so actions can be performed with limited manpower and time. After the Fukushima accident, Taiwan Power Company established ultimate response guidelines (URGs) and has implemented them in three operating NPPs. An URG is an event-based guideline developed to manage accidents caused by a compound disaster beyond the design basis. The purpose of this study is to find out the differences of RPV depressurization strategies between EOPs and URGs and to discuss the effect of different RPV depressurization strategies on fuel integrity. The plant responses and accident physical phenomena are simulated using MAAP5. The results show that the RPV water level should be maintained as high as possible and the RPV pressure should be controlled sufficiently low at the beginning of RPV emergency depressurization to avoid core uncovery and assure fuel integrity. The URG provides the better RPV depressurization strategy to respond to a beyond-design-basis accident and mitigate an anticipated severe accident consequence as early as possible.