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Division Spotlight
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.
Meeting Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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
DOE opens pilot program to authorize test reactors outside national labs
Details of the plan to test new reactor concepts under the Department of Energy’s authority but outside national laboratory boundaries—first outlined in one of the four executive orders on nuclear energy released on May 23—were just released in a request for applications issued by the DOE.
Gang Li
Nuclear Science and Engineering | Volume 180 | Number 2 | June 2015 | Pages 154-171
Technical Paper | doi.org/10.13182/NSE13-87
Articles are hosted by Taylor and Francis Online.
This investigation is to design a nonlinear pressurized water reactor (PWR) core load-following control system with self-stability for regulating the core power and axial power difference within a target band. A two-point–based nonlinear PWR core without boron and with a power rod and an axial offset rod is modeled. By proposing the gap metric of the core to qualify the core nonlinearity, the linearized multimodel single-variable core under case 1 (multivariable core under case 2) classified by two movable regions of the power rod is modeled. Linearized models of the core at seven power levels are chosen as local models of the core to substitute the nonlinear core model for each case. Based on H-infinity (H∞) control theories, the linear matrix inequalities method is adopted to design a H∞ output-feedback controller of every local model, which is a local controller of the nonlinear core of each case. In terms of the flexibility idea of control presented, the core load-following control system for each case is established. A theorem is deduced to analyze the global stability of the system of each case. Ultimately, simulation results show that the H∞ multimodel control strategy is effective for the core of each case.