2010 年 76 巻 763 号 p. 509-515
This paper presents a computational method of random vibration of the turbine blades using the multi-degree of freedom spectrum analysis. This computational method is applied to the cyclic symmetry method to the spectral analysis and enabled a large-scale calculation of the steam turbine blades. In this computational method, it especially focused on the turbine blade with one-ringed blade and grouped blade structures. We call this structure a compound periodic structure. The compound periodic structure has the feature from which the response of two or more modes is calculated with one harmonic number. Therefore, the mode characteristic is important to superpose the random vibration response. Also, the random vibration examination by a simple blade model was done. The calculation results were corresponding to the measurements well, and the validity of the computational method was confirmed.