滚动轴承局部损伤的完备预测模型与GID评估

Integrated model to predict vibration response of rolling bearings with localized defects and GRD assessment

现有的轴承局部损伤模型往往忽略了滚动体和支座的影响,因此所得振动特征误差较大。为了解决这个问题,提出了一种新颖的滚动轴承有、无故障完备预测模型,该模型将滚动体-套圈-支座的接触问题考虑为非线性Hertzian接触和多自由度质量-刚度-阻尼系统,进而应用Runge-Kutta数值方法计算了轴承局部损伤下的时、频域响应。最后,针对实际服役轴承系统运行状态的复杂性、不确定性及乏样本的特点,引入灰色关联度(grey incidence degrees)根据预测响应复合特征向量对滚动轴承的不同状态进行了定量评估,实验研究结果表明正确性和有效性。

With the current bearing models,there may appear bigger errors in the indentification of vibration characteristics,compared with the real situation because of neglecting the impacts of pedestal and rolling element.A novel prediction model was developed to obtain the vibration response in the case of existence of local defects in bearing system.In the analytical formulation,the contacts between the rolling elements and the races were considered as non-linear springs.The contact forces were calculateded by using the Hertzian contact deformation theory and the bearing system was modeled as a multi-degrees-of-freedom system.The implicit type of numerical integration technique,the Runge-Kutta method,was used to solve the non-linear differential equations iteratively.A computer program was developed to simulate surface defects of the components.Then the approach of grey incidence degree（GRD） was employed to investigate the condition assessment based on hybrid features obtained from the novel model.The new technique was experimentally evaluated using vibration signals measured on rolling bearings system with local defects,and good results were obtained,whcih verify the validity and effectiveness of the method proposed.