AGMA 10FTM16 PDF

In epicyclic gear sets aimed at aeronautical applications, planet-gears are generally supported by spherical roller bearings with bearing outer race being integral to the gear hub. This paper presents a new method to compute roller load distribution in such bearings where the outer ring can't be considered rigid. Based on well known Harris method, a modified formulation enables to account for centrifugal effects due to planet-carrier rotation and to assess roller loads at any position throughout the rotation cycle. New model load distribution predictions show discrepancies with results presented by Harris, but are well correlated with 1D and 3D Finite Element Models. Several results validate the use of simplified analytical models to assess the roller load distribution instead of more time consuming Finite element Models. The effects of centrifugal effects due to planet-carrier rotation on roller loads are also analyzed. Finally the impact of the positions of rollers relative to the gear mesh forces on the load distribution is shown.