A Stochastic Method for Nuclear Power Plant Diagnosis

  • R. B. Perez
  • R. T. Wood


The value of using neutron noise descriptors, especially the power spectral densities (PSDs) of ex-core detectors, to monitor core barrel motion and fuel element vibrations in pressurized water reactors (PWRs) is well established.1–6 Indeed, in the mid-frequency range (1–20 Hz), PWR neutron noise is dominated by vibration peaks in the neutron PSD that result from the motion of reactor internals. A qualitative examination of such descriptors from a 1150 MWE Westinghouse PWR plant, revealed significant changes in the plant’s noise signature (PSD) as its first fuel cycle proceeded. The purpose of this work is to use a mathematical model of the interaction between small mechanical motions and the core neutronics to provide a tool for quantitative investigation of the PSD structure in the vibrational frequency range.7


Power Spectral Density Fuel Element Fuel Assembly Fuel Cycle Neutron Detector 
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Copyright information

© Plenum Press, New York 1989

Authors and Affiliations

  • R. B. Perez
    • 1
    • 2
  • R. T. Wood
    • 1
    • 2
  1. 1.The University of TennesseeKnoxvilleUSA
  2. 2.Oak Ridge National LaboratoryOak RidgeUSA

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