Acoustic Resonance in an Axial Multistage Compressor Leading to Non-Synchronous Blade Vibration

Abstract Significant non-synchronous blade vibrations (NSVs) have been observed in an experimental three-stage high-speed compressor at part-speed conditions. High-amplitude acoustic modes, propagating around the circumference and originating highly loaded stage-3, coherence with structural vibration mode. In order to understand occurring phenomena, a detailed numerical study has carried out reproduce mechanism. Unsteady full-annulus Reynolds-averaged Navier–Stokes simulations of whole setup performed using solver elsA. The results revealed development modes which are partially trapped annulus resonance aerodynamic disturbance rotor-3. is identified as unsteady separation boundary layer indicate that frequency phase adapt match those wave therefore governed by propagation Furthermore, clearly show modulation rotor blades, leading change circumferential numbers while passing row. To analyze if effect self-induced vibration, non-coherent mode imposed simulations. Even high amplitude, formerly did not its number. This phenomenon relevant modern designs, since appearance axially waves can excite they coincide eigenmode, presented experiments.