8 research outputs found
In-situ high-resolution measurement of RHF nuclear fuel plates' spacing
International audienceMost of the High Performance Research Reactors (HPRR) are made of plates undergoing a limited swelling during irradiation. Measuring the fuel thickness or the inter-plate distance is then a promissing way to obtain information on the fuel element irradiation history. The experimental constraints are however quite heavy due to the aimed resolution and the element geometry. In order to perform such measurements, a high resolution ultrasonic device was designed. It was thinned down to 1 mm in order to be inserted into the reactor water-channel. The system is then excited with a 120 MHz central frequency burst and the distance measurement is carried out through the ultrasonic waves' time of flight estimation. A series of experiments was performed on a full size irradiated fuel element of the "Institut Laue-Langevin" reactor proving the feasibility of real-time in-situ measurements
Radiation resistance of high frequency ultrasonic devices for distance measurement in the RHF
The fuel element plates of research reactors are subjected to swelling phenomena. These structure modifications impact an initial inter-plate distance of 1.8 mm. An ultrasonic device has been developed to investigate this parameter. With a 1 mm thickness, it relies on two transducers linked to an
electronic system. The feasibility of the distance measurement has been proved in a previous study and the irradiation impact on the transducer components is here studied. To do so, a radiation resistance experiment was realized in the Arc-Nucleart Institute of Grenoble. It allowed the study of the influence of radiations on the device active and passive componentsâ characteristics
Tenue aux radiations de capteurs ultrasonores haute fréquence dédiés à la mesure de distance au sein de réacteurs à haut flux
International audienc
Tenue aux radiations de capteurs ultrasonores haute fréquence dédiés à la mesure de distance au sein de réacteurs à haut flux
International audienc
CaractĂ©risation ultrasonore de distances inter-plaques au sein dâun rĂ©acteur RHF
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