关键词: 叶片, 振动响应, 非线性, 激振力, 共振

Abstract: The difficulties found in solving the forced vibration equation of turbine blades are mainly the problem how to determine the exciting force acted on blades and the choice of an appropriate computation model. A nonlinear strain-displacement relationship is therefore developed in terms of the exciting force acted on turbine blades. Then, based on virtual work principle, a forced vibration equation of the blades which were twisted and bended to a certain degree is given. Further, a response function to blades' vibration is given by iterative process for relevant vibration mode, thus showing the response conditions to resonance of blades. A practical question is exemplified to analyze the response to blades' vibration/resonance. The results reveal that the response to blades' vibration depends mainly on such factors as the natural frequency of blades, vibration mode, frequency of exciting shock and exciting force or a harmonic component and, if taking beat frequency from the non-resonant response curve and the relationship among blades' natural frequency ω, exciting shock frequency ωe and the angular velocity of exciting force moving peripherally around blades, ωN, is ω = ωe = nωN(n = l,2,&mellip;,∞), the blades resonate.