Reduction of Resonant Stress of Turbine Blade by Use of Asymmetric Vane Spacing (Effect of Multi-resonance on Reduction of Vibratory Stress)

摘要

It is common knowledge that asymmetric vane spacing can result in decreased levels of the excitation at specific frequencies. In this paper, the resonant response reduction of turbine blades due to asymmetric vane spacing is studied theoretically for the most probable asymmetric vane in which the vane count of the upper and lower half is slightly different. First, a method for predicting the vibratory stress of the blade for the asymmetric spacing vane is proposed including the effect of the multi-resonance due to the excitation force clustered around the harmonic corresponding to the number of the vane count.