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On-line Determination of the MTC (Moderator Temperature Coefficient) by Neutron Noise and Gamma-Thermometer Signals

  • C. Demazière
  • I. Pázsit
Part of the Power Systems book series (POWSYS)

Abstract

The estimation of the Moderator Temperature Coefficient of reactivity (MTC) by noise analysis is investigated theoretically. It is shown that the main reason of the MTC underestimation by noise analysis that was noticed experimentally previously lies with the heterogeneous structure of the moderator temperature noise throughout the core. The resulting deviation of the reactor response from point-kinetics only accounts for a negligible part. Therefore a new MTC noise estimator is proposed. This estimator relies on the core average temperature noise that has to be evaluated with a proper core weighting function. The coolant temperature noise has to be measured in many points of the reactor so that the core average temperature noise could be approximated. Gamma-Thermometers (GTs) could be used for that purpose since it is demonstrated (both theoretically and via real measurements) that in the frequency range of interest for the MTC estimation they work as thermocouples.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2002

Authors and Affiliations

  • C. Demazière
    • 1
  • I. Pázsit
    • 1
  1. 1.Department of Reactor PhysicsChalmers University of TechnologyGöteborgSweden

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