Abstract：For rubbing faults caused between large rotating machinery blades and casing, a dynamic model of cantilever plate attached to a rotating rigid hub is established. The equation of motion is derived to include centrifugal stiffening effect by using Hamilton's principle. Based on the experimental and finite element analysis results of rubbing forces, approximate mathematical expressions are proposed. And analytical solutions for hub-plate system are obtained. Compared with the experimental results, models and methods are proved to be accurate. Their respective applicable conditions of the blade's beam and thin plate model are discussed. The influence of rotation speed on rubbing dynamic response is analyzed. It is showed that analytical solutions are accurate, and the thin plate model which can fully reflect the dynamic characteristics of a blade in the case of various rubbing is more accurate and reliable than the beam. Furthermore, as rotation speed increase, rubbing force causes amplitude of the thin plate in free end sudden change, which is important reason for loss corner faults or even break failure of blades in engineering.
2013, Vol. 34 
