Abstract
The gear is a cyclic symmetric structure, and each tooth is subjected to a periodic mesh force. These mesh forces have the same phase difference tooth by tooth, which can excite gear vibrations. The mechanism of additional axial force caused by gear bending is shown and examined, which can significantly affect the stability of a self-excited thin spur gears vibration. A mechanical model based on energy balance is then developed to predict the contribution of additional axial force, leading to the proposed numerical integration method for vibration stability analysis. By analyzing the change in the system energy, the occurrence of the self-excited vibration is validated. A numerical simulation is carried out to verify the theoretical analysis. The impacts of modal damping, contact ratio, and the number of nodal diameters on the stability boundaries of the self-excited vibration are revealed. The results prove that the backward traveling wave of the driven gear as well as the forward traveling wave of the driving gear encounter self-excited vibration in the absence of sufficient damping. The model can be used to predict the stability of the gear self-excited vibration.
Highlights
Gears are commonly used in machines, automobiles, wind turbines, and aerospace industries as a transmission component
According to the theoretical analysis of self-excited vibration in thin spur gears, the calculation program of the proposed method is developed by using Fortran language
The parameters of the thin spur gear used in this numerical simulation are listed in Table 1, with radius of the rim r1 = 95 mm, radius of the hole r2 = 25 mm, thickness h = 4 mm, and the number of teeth z = 50
Summary
Gears are commonly used in machines, automobiles, wind turbines, and aerospace industries as a transmission component. The status of the operational gear significantly influences the performances of the machines. In order to meet specific operational requirements, some gears are designed to be thin. The bending stiffness and the associated flexural natural frequencies are relatively low, which could lead to some kind of dynamic phenomena, such as transverse vibration. Recent research on fracture failure of aero-engine gears showed that the characteristics of the gear crack were found to be typical fatigue fractures caused by transverse vibrations. The operational conditions showed that there was no resonance during the operation, which indicates that there must be some other reasons that could cause the fracture. Gears’ self-excited vibration was suspected to be the main reason, but this needs to be verified
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
