Forced resonance induced by rotor–stator interaction (RSI) is a primary driver of high-cycle fatigue (HCF) failure in aero-engine blisks. To overcome the inability of traditional non-contact excitation methods to replicate authentic three-dimensional aerodynamic forces and the predictive biases of pure numerical approaches regarding complex flow excitation energy, this study investigates the forced resonance characteristics of a rotating blisk using a novel aerodynamic excitation system through integrated numerical and experimental approaches. First, a one-way fluid–structure interaction (FSI) framework, coupling the Nonlinear Harmonic (NLH) method with Finite Element Analysis (FEA), was established to efficiently reconstruct the unsteady aerodynamic loads on blade surfaces. The analysis reveals an excitation mechanism dominated by the upstream propagation of the downstream potential field, based on which the numerical resonance response was predicted. In addition, investigating rotor–stator axial clearance as a key variable indicates that there is a strictly monotonically decreasing dependence of the aerodynamic excitation magnitude on the rotor–stator axial clearance. However, the spatial patterns of the primary first-order harmonic excitation remain relatively insensitive to changes in the rotor–stator axial clearance. Finally, by leveraging these excitation characteristics, broadband aero-resonance of the first three modes was successfully induced within the 2600 Hz frequency range under experimental conditions. This validates both the effectiveness of the experimental apparatus and the fidelity of the numerical model. This research not only clarifies the excitation mechanism under vortex generator-induced RSI but also provides a novel testing platform and theoretical framework for rotating modal analysis in advanced propulsion systems.
Gu et al. (Mon,) studied this question.