Abstract: The receptance method for the coupled blade bending and shaft torsion vibration response calculation of rotating machinery is presented. It can be used to analyze the coupled transient or stable vibration with any number of blades. It is shown that there exists strong coupling between the two kinds of vibration. The blade critical frequencies are decreased while the shaft critical frequencies are increased in the coupled system. The two kinds of vibration will be induced simultaneously under the stable or transient electrical disturbance. The force and moment of the blade root will reach a large peak in a short time, which can lead to the damage of the blade.

Key words: Blade, Botor, Vibration