Mechanism and Suppression of Acoustic Resonance in Compressors via Serial Flat-Plate Cascades

Abstract

Abstract This study adopted a combined experimental and numerical approach to investigate acoustic resonance phenomena in aseroengine compressors. Experimental results demonstrate that intense acoustic resonance occurs at a characteristic frequency of 1,402 Hz when the rotational speed is within the range of 9,780 – 1 0,020 r / min , with a peak sound pressure level reaching 152 dB. Subsequently, four serial flat-plate cascade models were established and analyzed via the Lighthill acoustic analogy. The model with an interplate spacing ratio d / h = 3 and a chord-to-thickness ratio c / h = 7 exhibits first-order resonance at 610 Hz. At this frequency, the sound pressure level exceeds 170 dB, accompanied by distinct frequency-locking behavior. In contrast, the second-order acoustic resonance at 1,140 Hz remains relatively weak. Reducing the length of the downstream plate increases the resonance frequency to 630 Hz and reduces the sound pressure level to 160 dB. Increasing the plate spacing suppresses first-order resonance, limiting the sound pressure level to 140 dB, but strongly excites intense second-order acoustic resonance exceeding 160 dB. The combined strategy of enlarging plate spacing and reducing plate thickness effectively suppresses acoustic resonance altogether, maintaining the sound pressure level at 140 dB. These findings indicate that strategic adjustments of geometric parameters can effectively modulate vortex-acoustic coupling mechanisms, providing important references for suppressing acoustic resonance in compressors.