Experimental Investigation of Bladed Disk Dynamics at Design Speed Under Synchronous Vibration

Abstract

This work presents an experimental and computational investigation of a rotating bladed disk excited with air jets. The bladed disk is accelerated through critical speeds corresponding to specific engine orders of interest while air jets apply a constant forcing. These conditions induce synchronous vibrations in the blades. The experimental results were used to compute mistuning and damping values of the system, which were used in the computational analyses. This work uses a parametric reduced order model (PROM) that can adjust the system stiffness based on the rotational speed within the reduced space. Component mode mistuning was coupled with the PROM to create a mistuned model capable of capturing the mistuned system dynamics. Computational values for the blade frequency, amplitude, and damping were compared with experimental results to show how the computational model presented in this work can be used to characterize a rotating bladed disk.