[1A3] Identification of the reasons for shaft vibration non-stationarity of the IBR-2 research reactor mobile reflector
V Sizarev1, D Ognerubov1, A Volkov1, S Timofeev1, A Sokolova2 and F Balitsky2,3
1JSС NIKIET, Russia
2IMASH RAN, Russia
3Spectrum Engineering, Russia
The paper is devoted to investigations of root causes of a temporary increase of axial shaft vibrations for the IBR-2 research reactor movable reflector, which kept repeating from one operation cycle to another one. It happened at the beginning of each cycle and then axial shaft vibrations and case vibrations calm down and the unit came back into normal operation condition. Of most interest was the vibrational state of the front support located in the immediate vicinity of the reactor. A finite element reflector model was developed. A thermophysical calculation was carried out, according to the results of which the temporary unsteadiness of the temperature fields was analysed until the time of the onset of the stationary state. The calculation of the dynamic strengths confirmed that the reflector’s operability, taking into account the occurrence of non-stationary temperature fields, is preserved and the requirements for cyclic strength are fulfilled.
