Experience with the application of noise analysis based measurement techniques to the Dodewaard natural circulation cooled boiling water reactor

For many years, noise analysis based measurement techniques have been applied to the Dodewaard natural circulation cooled boiling water (183 MWth, The Netherlands). The purpose of the measurements is to provide data for computer code validation, and for studies into the physics of the reactor, especially with respect to natural circulation. Of main interest are the thermal-hydraulic/reactor-kinetic stability and the natural circulation flow as an important stability parameter. A wide range of operating conditions has been investigated. The noise analysis methods applied are the cross-correlation flow measurement technique, the cross-correlation velocity measurement technique, in-core noise two-phase flow monitoring ad void detection, and reactor stability monitoring. The analysis techniques are described, and the results of measurements during shut-down and start-up of the Dodewaard BWR are discussed. A concise interpretation of the results is presented. (authors)