Dynamic behavior of a rotor-misaligned spline coupling system

Meshing force model of a misaligned spline coupling was derived, dynamic equation of a rotor system considering influence of misaligned spline coupling was established based on finite element analysis. The influence of the meshing force on the rotor-spline coupling system was simulated with numerical integration method. Theoretical analysis and simulation results showed that meshing force of a spline coupling is related to its structural parameters, transmitted torque, static misalignment, dynamic vibration displacement, and so on; stiffness of a coupling is not a constant, it relates to dynamic vibration displacement and depends on static misalignment. Dynamic behavior of a rotor-spline coupling system revealed that 1X-rotating speed is the main frequency of the system response when there is no misalignment; while 2X-rotating speed appears with some misalignment; moreover, when misalignment increase, the shaft center orbit deviates the origin and magnitudes of all frequency components arise, the system vibration becomes complex. This research results can provide a reference for trouble-shooting of rotor systems connected with spline coupling.