Aiming at the rubbing fault between flexible blade and rigid casing, taking a bar blade as object of study, simplify the blade as rotating cantilever beam model, in addition deduce the analytic model using Hamilton's principle and variation equation. According to the decentration relation between disc and casing, deduce the clearance changing function, on the basis of which to determine whether rubbing occurs. Considering the effect of centrifugal rigidization, spin softening and Coriolis force, the numerical simulation of blade-casing rubbing is done by using Newmark-β explicit numerical integral algorithm. The results show that due to the Coriolis force, the coupling occurs between the blade axial displacement and horizontal displacement. After the rubbing force disappears, the free vibration period of axial displacement is bend dynamic frequency. Under high revolving speed, the influence of horizontal displacement to axial displacement is weakened, and more randomness occurs in the direction of bend.
TAI Xing-yu;MA Hui;TAN Zhen;WEN Bang-chun .
Dynamic characteristics of the continuous medium rotating beam model with rubbing fault[J]. Journal of Vibration and Shock, 2013, 32(18): 43-48
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