Development of a numerically efficient model for the dynamics of revolute clearance joints in adjustable stator cascades

The consideration of system resonances plays an important role in machine development and layout especially in case of systems with high operational velocities. Unfortunately, prediction of resonance frequencies becomes difficult if systems contain clearance joints, hence making reliable simulations using commercially available software tools nearly impossible. Within this thesis a simulation method is developed and employed which is capable of predicting the dynamical behavior of multibody systems in a reliable manner while considering friction and impacts within clearance joints. Special attention is paid to plausible and computationally efficient modeling of nonlinear contact events. The simulation methodology is experimentally validated and subsequently employed in combination with further experimental investigations to analyze the dynamical behavior of adjustable stator vane cascades. Dominant nonlinear resonances are identified, and the corresponding vibration shapes are characterized. Furthermore, the possibility of using the clearance within the joints for minimizing the resulting system resonance amplitudes is demonstrated.