Nuclear Technology -- ANS / Publications / Journals / Nuclear Technology

About ANS
- ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
About Nuclear
- Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
Communities
- Division Spotlight
  Nuclear Nonproliferation Policy
  The mission of the Nuclear Nonproliferation Policy Division (NNPD) is to promote the peaceful use of nuclear technology while simultaneously preventing the diversion and misuse of nuclear material and technology through appropriate safeguards and security, and promotion of nuclear nonproliferation policies. To achieve this mission, the objectives of the NNPD are to: Promote policy that discourages the proliferation of nuclear technology and material to inappropriate entities. Provide information to ANS members, the technical community at large, opinion leaders, and decision makers to improve their understanding of nuclear nonproliferation issues. Become a recognized technical resource on nuclear nonproliferation, safeguards, and security issues. Serve as the integration and coordination body for nuclear nonproliferation activities for the ANS. Work cooperatively with other ANS divisions to achieve these objective nonproliferation policies.
Events
- Meeting Spotlight
  International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
  April 27–30, 2025
  Denver, CO|The Westin Denver Downtown
Standards
- 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!
Publications
- Latest Magazine Issues
  Apr 2025
  Jan 2025
  Latest Journal Issues
  Nuclear Science and Engineering
  May 2025
  Nuclear Technology
  May 2025
  Fusion Science and Technology
  April 2025
- Latest News
  Nuclear's future discussed at MURR expansion
  ANS Executive Director/CEO Craig Piercy recently spoke on nuclear power’s potential for answering today’s energy demands as part of the Distinguished Lecture Series at the University of Missouri. He also took part in the ribbon cutting for a large addition to the University of Missouri Research Reactor (MURR).
Search

In this paper, the effect of a pin-by-pin thermal-hydraulic feedback treatment on the core characteristics at a steady-state condition is investigated using a three-dimensional fine-mesh core calculation code. Currently, advanced nodal codes treat the inside of an assembly as homogeneous, and the temperature distribution inside a node is usually ignored. Namely, the fuel temperature is estimated from the assembly average power density, and the moderator temperature is calculated from the nodewise closed-channel model. However, the validity of a flat temperature distribution inside a node has not yet been investigated, because a three-dimensional pin-by-pin whole-core calculation must be done for comparison. A three-dimensional pin-by-pin nodal-transport code for a pressurized water reactor (PWR) core analysis, SCOPE2, was used in this study since it can directly treat the pin-by-pin feedback effect. A whole-core subchannel analysis code was developed to enhance the thermal-hydraulic capability of SCOPE2. The pin-by-pin feedback models for fuel and moderator temperature were established, and their impact on the core characteristics was investigated in a 3 × 3 multiassembly and the whole PWR core geometries. The calculations showed that modeling of the pin-by-pin temperature distribution revealed a negligible effect on core reactivity and only a slight impact on the radial peaking factor. The difference in the radial peaking factor that is exposed by the pin-by-pin temperature modeling is less than 0.005 in the test calculations.