RESEARCH ON VIBRATION CHARACTERISTIC FOR VARIABLE ROTATING VELOCITY BLADES

摘要

As engine speed increase, centrifugalstiffening causes a blade’s natural frequenciesto increase. Because the frequencies of bendingmodes tend to increase at a faster rate thanthose of torsion mode, the frequencies ofbending and torsion modes are disposed tocross. Aimed at the configuration and operationcharacteristics of the blades of the aero engine,based on sheet bending theory, considering thecentrifugal load, the frequency and mode shapeof the blades are studied by the beam functioncombination method. Considering the differentengine speed, aero elastic differentialintegration method for differential equation areresearched. The theoretical foundation of thefrequency and mode shape research oncantilever sheet are obtained. The new methodsof investigation on frequencies and mode shapehave been studied. The given frequency andmode shape solutions are rather practical forthe blade fatigue detecting, what’s more, thetheoretical base of flutter designing for engineblade are supplied.