关键词: 颤振, 非定常流, 振荡叶栅, 最大相对厚度, 能量法, 分离

Abstract: By using computational fluid dynamics and structural dynamics methods, the 3D viscous unsteady flow around oscillating cascades is numerically simulated. Through the computation and analysis of unsteady aerodynamic forces loading on the cascades and aerodynamic work, the probability of blade flutter is predicted through the energy method. The flutter characteristics of linear blades and fan rotors with various thickness are numerically analyzed respectively, and the influence of blade thickness and its variation on flutter characteristics is initially studied. Through studying the structure of the unsteady flow field in vibrating cascades, the coupling relationship between flow separation on the suction surface and blade vibration is revealed. The research results can be used to study the effect of structure design parameters such as maximum thickness on the aeroelastic stability in the fan/compressor design, and it is of value for reference in turbomachinery flutter mechanism research.

Key words: flutter, unsteady flow, oscillating cascade, maximum relative thickness, energy method, separation