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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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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
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.
George J. Bohm, Amir N. Nahavandi
Nuclear Science and Engineering | Volume 47 | Number 4 | April 1972 | Pages 391-408
Technical Paper | doi.org/10.13182/NSE72-A22431
Articles are hosted by Taylor and Francis Online.
The dynamic analysis of the reactor internal structure in a typical pressurized-water reactor system, subjected to step, periodic, and seismic excitations, is presented. Employing the finite element approach of structural analysis, the governing differential equations describing the motion of the system are set up and integrated numerically in time. It is shown that the introduction of three types of structural elements, elastic, rigid and pin-joint members with nodes having three degrees of freedom, provides an adequate mathematical model for the solution of reactor structural dynamics problems. A main distinctive feature of this analysis is the application of “elements” global stiffness matrices in place of the standard structural global stiffness matrix. It is shown that this feature reduces the computer storage requirement and running time considerably. An examination of the system dynamic response characteristics indicates that when the clearance between the reactor internal components is relatively small, impact between various components could occur. The magnitude of the impact forces for periodic and seismic excitations is computed. Furthermore, a procedure for the calculation of the upper bound of integration time step is presented which ensures the numerical stability of the solution.