Verification of a spherical plain bearing finite-element model using scattered light photoelasticity tests

Spherical plain bearings are used on many components of Airbus aircrafts like engine-to-pylon and pylon-to-wing links. Their design is based on contact pressure distribution on spherical surfaces. Until now, empirical laws are applied to determine it, and the aim of this work is to develop a numerical modelling in order to validate the use of these laws. The assumptions on the numerical model and their significance have been verified and meas-ured by scattered light photoelasticity (SLP) on an epoxy replica of the bearing. The analysis of this type of bearing is difficult due to its three-dimensional behaviour and its spherical confined contact. The SLP technique allows getting information on stress fields inside an epoxy specimen with the analysis of photoelastic fringes. Comparing photoelastic fringes with simulated results, the finite-element model has been improved to be more representative of the real life bearing. In addition, some critical factors on the bearing behaviour have been obtained.