Simulation, experimentation and identification of frictional dampers: application to a satellite propeller

This work focuses on modelling the nonlinear dynamics of an industrial suspension system for a satellite propeller. Damping solutions were formerly designed for the system and the purpose is now to effectively describe its behaviour. The base idea consists in the application of the Dahl model, a parametric empirical and hysteretic model widely used in dynamic friction field. Some of the developed damping systems are investigated: Multilayer, a frictional damper consisting in thin plates bolted on the suspension arms, and Granular, a dense pack particle damper. The main modelling tools are, respectively, FEM and DEM; then a numerical SDOF model updated with a Dahl damper element is used to simulate the system aiming to identify the parameters of a reduced order model. Both the experimental and the simulation path are pursued to validate the consistency of the results. The other systems are also considered but in a less detailed way. Concerning Multilayer, the Dahl model describes well the experimental trend and the simulation procedure exposed gives reliable parameters for the case study. The wide simulation work around granular media damping returns interesting conclusions as well: dissipation mechanisms - in particular friction - are explored and related to the compacity revealing an optimum working point, Dahl model is applied to fit the global behaviour of a simplified version of the granular damper giving a fairly positive response. This report can be seen as a connection between the former design phase and the following wider research study aiming to build a solid predictive framework, capable of linking nonlinear reduced order models to industrial design variables in this kind of applications.