The effect of blade crack on mode localization in rotating bladed disks

The effects of blade crack on mode localization in rotating bladed disks ar e investigated in this study. A disk consisting of periodic shrouded blades is used to simulate the bladed disk of a turbo-rotor. Blades on the disk a re approximated as Euler-Bernoulli beams. A crack in the blade is regarded as a local disorder of the system. This local disorder might introduce the so-called mode localization phenomenon in this mistuned system. The Galerki n method is employed to derive the equation of motion of the mistuned syste m, with the blade crack. The effects of position, depth of crack and rotati ng speed on the localization phenomenon in the rotating blade-disk system a re studied. Numerical results indicate that the blade crack may be one of t he reasons for the occurrence of the localization phenomenon in the rotatin g bladed disk. (C) 1999 Academic Press.