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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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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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Norway’s Halden reactor takes first step toward decommissioning
The government of Norway has granted the transfer of the Halden research reactor from the Institute for Energy Technology (IFE) to the state agency Norwegian Nuclear Decommissioning (NND). The 25-MWt Halden boiling water reactor operated from 1958 to 2018 and was used in the research of nuclear fuel, reactor internals, plant procedures and monitoring, and human factors.
Frigyes Reisch
Nuclear Science and Engineering | Volume 26 | Number 3 | November 1966 | Pages 378-384
Technical Paper | doi.org/10.13182/NSE66-A17360
Articles are hosted by Taylor and Francis Online.
In a digital computer controlled system it is possible to monitor several variables almost at the same time and control the system according to the most critical one. This is called a sampled-data control system. The purpose of the paper is to demonstrate how to handle such a problem. A simplified reactor system including neutron kinetics and fuel and cooling medium kinetics with a simple control circuit is examined. It is assumed that the reactor has a great number of cooling channels, and it is necessary to check the exit temperatures of the cooling medium as the maximum value is the limiting factor. Sampling is performed to accomplish this. The temperatures are scanned and a comparison is made between the value stored in the memory and the point being measured. The higher of the two values remains in the one word memory. After checking all the temperatures, a pulse representing the temperature of the hottest channel is sent through the sampler to the regulator and the memory is cleared. A suitable method to study the stability is the z transform analysis. The procedures and logic followed are outlined here. First, the system is defined in the terms of Laplace transformation. Then the solving of the sampled system problem by the z transform theory is shown. A digital computer program is developed. The results of several calculations show the importance of choosing the right parameter combinations.