Optical tip clearance measurements for rotating disk characterization

An experimental study about the vibrational behaviour of two prototypes of a rotating disk by means of three optical sensors is presented. Both prototypes were assembled in a wind tunnel in order to reproduce real operation conditions. The optical sensors identified the vibration frequency and the nodal diameter of the first prototype by measuring the clearance of the disk to the casing of the wind tunnel. This method was also employed to check the improvements obtained with an upgraded design of the rotating disk, showing that the measuring system presents a great potential to perform non-contact evaluation of rotating components.