Torsional Stalled Flutter of Mistuned Cascades : Two Kinds of Blades of Different Natural Frequencies are Arranged Alternately

Abstract

The effects of mistuning on flutter suppression for a fully stalled cascade in pitching motion in which two kinds of blades, each with a different natural frequency, are arranged next to each other, are examined. Numerical results are obtained for several cases by changing the natural frequency of the blade, and some fundamental aspects are clarified. As a result, it is found that the flutter suppression effect is observed in the case of a fully stalled cascade well as an unstalled cascade, but the effect of the former is much stronger with small chane of mistuning compared to the latter. Furthermore, the effect is more remarkable for the turbine side compared to the compressor side.