The influence of anomalies in supporting structures on the validation of finite-element blade bearing models

Finite-element analysis is the only means to determine the load distribution of large slewing bearings considering flexible bearing rings and supporting structures. For reliable results, the plausibility of the models need to be validated. Previous attempts on validating a finite-element model of a slewing bearing against measurement results have indicated a huge dependence of the deformation on tolerances in the supporting structures. This dependence has not yet been explored in research in favor of a focus on tolerances of the bearing itself. The present work explores different irregularities of the flange that connects to the outer ring of the bearing and their effects on bearing deformation. The results show that single dents or bulges on the flange and inclined flanges of the adapter ring significantly change the load distribution and contact angles of the bearing. They also aggravate the risk of truncation. For the calculated fatigue life however, the bearings seem to be robust to these uncertainties for the shown load cases. The dimensions of the investigated tolerances are verified by comparing the resulting deformations of the bearing outer ring against experimental data.