Study on dynamic characteristics of the gear-dual-rotor system with multi-position rubbing

To reveal the mechanism of gear meshing induced rubbing and investigate the nonlinear dynamic response characteristics of a gear-dual-rotor system with multi-position rubbing, a new finite element model (FEM) of the gear-dual-rotor system considering the gear meshing excitation is established based on the in-house beam element code. Then, the fixed interface component mode synthesis method (FICMSM) is used to establish the reduced gear-dual-rotor dynamic model. A rotor-rotor rubbing model between the inner and outer rotors (IORs) and a rotor-stator rubbing model are built through vectors considering whirling velocities. In addition to the general concern about the low-frequency components around rotating frequencies and transversal responses with rubbing, more attention is given to the high-frequency components around the gear meshing frequency and the torsional responses. Finally, some interesting phenomena are found as follows: gear meshing is a new cause of partial rubbing. Some combined frequencies between the rotating frequencies of IORs and modulation frequencies between the meshing frequency and rotating frequencies are found in the transversal and torsional responses.