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 address this issue, a new sub-stiffness, named torsional stiffness, is introduced into the modified time-varying mesh stiffness (TVMS) model to quantify the effects of non-uniform loading caused by asymmetric 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 developed to assess the reliability of pitting defect evolution. A case study is presented to illustrate the proposed model and to analyze the effects of different pitting degree and location on the dynamic response and reliability of the gears. The results demonstrate that the dynamic response interval of the gear system is influenced by the uncertainty of both the degree and location of pitting. Furthermore, the same degree of pitting defects under asymmetric conditions exacerbates the anomalies of the dynamic response, in turn reducing the reliability of the gear system.