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Thermal Hydraulics
The division provides a forum for focused technical dialogue on thermal hydraulic technology in the nuclear industry. Specifically, this will include heat transfer and fluid mechanics involved in the utilization of nuclear energy. It is intended to attract the highest quality of theoretical and experimental work to ANS, including research on basic phenomena and application to nuclear system design.
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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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Remembering Joseph M. Hendrie
Joseph M. Hendrie
To those of us who knew Joe, even prior to his appointment as chair of the Nuclear Regulatory Commission, it is an understatement to say that he was a larger-than-life member of the nuclear science and technology enterprise. He was best known to the broader community for two major accomplishments: the design and construction of the High Flux Beam Reactor (HFBR) at Brookhaven National Laboratory and the creation of the standard review plan (SRP) for the U.S. Atomic Energy Commission.
In addition to the products of these endeavors becoming major fundaments to their respective communities, they were uniquely Joe. The safety analysis report for the HFBR was written essentially single-handedly by him. This was true of the SRP as well, which became the key safety review document for the NRC as it performed safety reviews for the growing number of power reactor applications in the United States. His deep technical knowledge of nuclear engineering and his extraordinary management skills made this possible.
Pengfei Wang, Jiashuang Wan, Shoujun Yan, Yang Liu, Fuyu Zhao
Nuclear Technology | Volume 187 | Number 3 | September 2014 | Pages 243-259
Technical Paper | Fission Reactors | doi.org/10.13182/NT13-111
Articles are hosted by Taylor and Francis Online.
This paper presents the performance evaluation of an improved mechanical shim (MSHIM) control strategy that is implemented in the AP1000 reactor by a digital rod control system. The MSHIM control system automatically controls the core reactivity and axial power distribution using gray and black M control banks (M-banks) and an axial offset (AO) control bank (AO-bank). The M-banks and AO-bank are independently controlled by the power control subsystem and the AO control subsystem. In the original MSHIM strategy, the power control subsystem takes precedence, and the AO-bank is blocked from moving when a demand signal exists for the movement of the M-banks. This rod control logic can minimize the potential for interactions between the two rod control subsystems and guarantee the safety and stability of the MSHIM control system. However, the AO control capability is weakened at the same time. Thus, Westinghouse has improved this core control strategy, which gives preference to the AO-bank when both the AO-bank and the M-banks have a demand to move in the same direction. In this paper, first, the coupling characteristic of the MSHIM control strategy is analyzed to illustrate the coupling effect between the two rod control subsystems. Then, both the original and the improved MSHIM control strategies are applied to AP1000. It has been demonstrated by the MSHIM load-follow and load regulation simulation results that the improved strategy not only can provide much tighter AO control but also can reduce the total control rod movement without compromising the coolant average temperature control. Therefore, the improved MSHIM strategy can provide much better reactor control capabilities than the original strategy.