Experimental Vibroacoustic Measurements of a Centrifugal Compressor Stage for Oil & Gas Applications

Designing adequate noise mitigations on centrifugal compressors for Oil & Gas applications to meet the noise regulation requirements for industrial plants requires an accurate prediction of the radiated noise. Further investigation of centrifugal compressors' noise emission is still needed to develop predictive sound models, which require a thorough understanding of all noise generation mechanisms involved. This paper presents the results of an experimental vibroacoustic analysis conducted on a centrifugal compressor equipped with one closed impeller. Vibroacoustic measurements were performed in three different operating conditions at various working points, aiming to characterize the noise emission of the compressor stage. The results identified the main tonal components of the compressor stage and the noise generated by auxiliary machinery under different working conditions. Consistent with findings from other studies from the literature, a strong influence of the rotational impeller speed on the radiated sound pressure is observed. Moreover, the results propose an experimental comparison between vaned and vaneless diffuser configurations, highlighting higher sound pressure levels radiated with a vaneless impeller design. The paper concludes by highlighting the difficulties related to the experimental testing of such machinery and the significant influence of noise emitted by auxiliary equipment.