Abstract
This paper descibes 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 grouped blade structure. The grouped blade structure has the feature from which the response of two or more modes is calculated with one harmonic number. Also, the random vibration examination by a simple blade model was performed. Both modal damping and random excitation PSD (Power Spectrum Density) are the most important factors of the calculation. The experimental results demonstrated that the random vibration response of the turbine blade can be estimated by this calculation method.
