Transverse mode localization in a dual-span rotating shaft

摘要

In this paper, transverse mode localization in a dual-span rotating shaft is studied. The shaft is elastically supported by transverse and rotational springs at an intermediate point and at both ends. A Timoshenko beam model including the effects of axial loads is employed, and a small disorder in the span length is introduced in the study of the mode localization. The exact eigensolutions of the systems are obtained by the phase closure principle. Based on actual values of typical bearing stiffness applied in turbo machinery, the effects of support stiffness, rotation speed and axial load on the mode localization are examined. These results are compared with those obtained from the Rayleigh shaft model to assess the effects of shear deformation. It is shown that mode localization depends strongly on the modelling of the bearing support.