Abstract
In this paper we presented results of fundamental study to introduce the wavelet transform to vibration diagnosis for a turbine. It is required to detect typical vibration of the turbine accurately. The wavelet transform is used in many fields because it is able to visualize a phenomenon in a time-frequency domain. Modern power plants usually use one-high pressure and one or two lower pressure turbines. We made a turbine model with 3 rotors supported with journal bearings to simulate contact vibration, oil whip, and clearance vibration. The vibration phenomena were measured with vertical and horizontal displacement meters at the rotors, and with vertical and horizontal accelerometers at the bearings. The vibration phenomena were visualized in the time-frequency domain by the wavelet transform. This paper especially shows the results of the acceleration signals. It is found that the dynamic spectra obtained by the wavelet transform of the acceleration signals are different for each vibration. Therefore, this method is able to distinguish the vibration phenomena. And furthermore, the contact point is localized by the proposed method.
