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Materials Science & Technology
The objectives of MSTD are: promote the advancement of materials science in Nuclear Science Technology; support the multidisciplines which constitute it; encourage research by providing a forum for the presentation, exchange, and documentation of relevant information; promote the interaction and communication among its members; and recognize and reward its members for significant contributions to the field of materials science in nuclear technology.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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Latest News
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.
Amir N. Nahavandi, Richard F. von Hollen
Nuclear Science and Engineering | Volume 20 | Number 4 | December 1964 | Pages 392-413
Technical Paper | doi.org/10.13182/NSE64-A20982
Articles are hosted by Taylor and Francis Online.
A one-dimensional space-dependent dynamic analysis of boiling water reactors, for direct, indirect or dual cycle systems with forced or natural circulation is presented. The analytical model consists of space-dependent neutron kinetics equations for the reactor core, and flow-conservation equations for the reactor coolant system developed in terms of length along the flow path and time. The resulting set of non-linear partial differential equations is expressed spatially in finite-difference form and integrated numerically in time to obtain the space- and time-dependent system variables. The effect of system-pressure variation is neglected. The mathematical model and numerical procedures employed in this study are verified against available test data from the Levy and Beckjord experimental boiling loop. Analytical predictions of the threshold of instability and the frequency of oscillations are shown to be in agreement with the test data. Studies of the uncontrolled and controlled behavior of a 110-MWe direct cycle boiling water nuclear power station confirm that, in contrast with natural-circulation loops, forced-circulation boiling systems have a high degree of hydrodynamic stability. However, an inappropriate selection of control-system parameters may induce nuclear power instability in both natural- and forced-circulation plants. The theoretical approach presented maybe successfully employed as a powerful tool for the determination of the system stability, as well as for evaluation of the degree of effectiveness and relative merits of various system power-control techniques.