TAPERED TIMOSHENKO FINITE-ELEMENTS FOR ROTOR DYNAMICS ANALYSIS

Finite element idealizations of rotor systems, which include shafts with significant taper angles, often model the tapered sections using stepped, uniform cross-section elements. As part of a study of the shock response of rotor-bearing systems, two tapered beam finite elements have been developed. In one a linear approximation is used for the geometrical properties yielding closed form expressions for the element matrices. Scaling factors are incorporated to compensate for errors introduced by the linear approximation. In the other element exact expressions are used with a numerical integration. Included in the analysis are translational and rotational inertia, shear deformation, gyroscopic moment, axial torque, viscous and hysteretic material damping and mass eccentricity. © 1990.