Session: 28-07 Dynamic Response of Bladed Disks

Paper Number: 122504

122504 - Forced Response of Bladed Disks With Excitation Variability 

The prediction of forced response of mistuned bladed disk remains an important topic in turbomachinery design. The investigation of mistuning focuses usually on the blades in terms of their different structural properties. The excitation mechanism is considered to be mainly caused e.g. by the wakes from an upstream and the potential field from a downstream blade row. In recent years, it has been demonstrated that the Tyler-Sofrin modes (scattered or spinning modes) may affect blade forcing significantly and cause variable forcing amplitude on individual blade in multistage turbomachinery. As a result, the vibration is localized at some of blades receiving greater forcing amplitude, which leads to higher damage risk for those blades. Depending on the configuration of turbomachinery, excitation arising from Tyler-Sofrin modes may have several frequency components, which requires multi-harmonic balancing method (MHBM) for FRF computation in presence of nonlinear blade couplings. This paper aims to develop the computation method for linear and nonlinear FRF of a bladed disk under variable excitation caused by Tyler-Sofrin modes. In addition to excitation variability, the mistuning property of blades is studied by investigating their geometric deviation with regard to the nominal blade geometry. The study of geometric mistuning is performed on an academic test rig.

Presenting Author: Yue Xiao Leibniz University of Hannover

Presenting Author Biography: Research assistant at institut of dynamics and vibration research in Leibniz University Hannover

Authors:

Yue Xiao Leibniz University of Hannover
Lars Panning-Von Scheidt Leibniz University Hannover, Institut of Dynamics and Vibration Research