Propagation of friction parameter uncertainties in the nonlinear dynamic response of turbine blades with underplatform dampers

Underplatform dampers are widely used in turbomachinery to mitigate structural vibrations by means of friction dissipation at the interfaces. The modelling such is challenging because high variability observed experimental measurements contact parameters. Although this not commonly accounted for state-of-the-art numerical solvers, probabilistic approaches can be implemented include it dynamics simulations order significantly improve estimation damper performance. aim work obtain uncertainty bands dynamic response turbine blades equipped with including interfacial This experimentally quantified from a rig and generate combining deterministic solver stochastic Polynomial Chaos Expansion (PCE) models. thus obtained validated against data an underplatform test rig. In addition, PCEs also employed perform variance-based global sensitivity analysis quantify influence parameters on variation nonlinear via Sobol indices. highlights that each parameter vibration amplitude strongly varies over frequency range, indices effectively analyse uncertainties associated structures interfaces providing valuable insights into physics complex systems.