239 / 2025-06-15 16:45:38

Dynamic analysis and reliability modeling of spur gears considering asymmetrical pitting interval uncertainties

asymmetrical pitting,time-varying meshing stiffness,Chebyshev interval method,dynamic response interval,reliability modeling

Special Sessions > SSL 07 Belief reliability theory and its application in smart operation and maintenance

Asymmetrical pitting is a common failure mode for spur gears in continuous operation. Accurately evaluating the dynamic characteristics and reliability of pitted gears is challenging due to the uncertainty in pitting degree and location caused by the randomness of operating conditions and initial defect distribution, which is further propagated through the differential equations in the dynamics model. To tackle this problem, a new torsional sub-stiffness is added to the time-varying meshing stiffness (TVMS) model to quantify the effects of non-uniform loading caused by asymmetrical pitting. Based on this, a Chebyshev interval method is employed to construct an interval dynamic model that rapidly calculates the dynamic response intervals, taking into account the uncertainty of pitting degree and location. Furthermore, a time-dependent reliability model is constructed to evaluate the gear system’s reliability under the evolution of pitting defects. A case study is employed to clarify the proposed model and to discuss the effect of pitting degree and asymmetrical location on the dynamic response and reliability of gears. The results demonstrate that the gear system’s dynamic response interval is influenced by the uncertainty of both the cumulative pitting length and the pitting offset location. Furthermore, the same degree of pitting defects under asymmetric conditions exacerbates the anomalies of the dynamic response, in turn reducing the gear system’s reliability.