Assessment of a Microslip Model for the Numerical Simulation of Underplatform Damper Dynamics

This thesis work was developed in the Department of Mechanical and Aerospace Engineering (DIMEAS) at Politecnico of Turin. It focuses on under-platform damper kinematics and its damping capabilities estimation by means of a dedicated, improved numerical model which includes the e ffects of a phenomenon called micro-slip.Taking over the advantage of AERMEC laboratory's test rigs set to investigate the relationship between the blade platform displacements and the contact forces, it was possible to assess the developed model against the observed experimental data. After an overview of the existing experimental-numerical method developed by the AERMEC group during the previous years, with particular relevance to the weaker cases in which the experimental has a minor match to the simulation, index of a possible neglected micro-slip e ffect in the contact model. Therefore the improved contact model will be established and later applied on a series of cases on two types of contact geometries. The results of simulations will be compared and analysed closely in order to have a better understanding of the working ranges in which the phenomenon of micro-slip has a wider impact on the overall energy dissipation.