The purpose of this study was to identify the noise sources and noise characteristics of the suction housing, and to acoustically analyze the noise source to identify noise reduction measures. For this purpose, measurements of sound pressure, vibration, and intensity were collected during normal, steady-state operation of the suction housing. Then, the presence or absence of resonance was determined
by comparison with the BPF that was identified through the process of measuring the sound pressure level. Detailed 3D modeling was conducted using reverse engineering, allowing a model for acoustic analysis to be designed by extracting the inner
boundaries separately after the 3D modeling was conducted. For the modeling of an analytic object using the reverse engineering, an analytic model was designed that was exactly consistent with the full-scale one, allowing more accurate analysis. In particular, the acoustic FRF inside the suction housing was obtained by applying
BEM. The characteristics of the acoustic FRF in the suction housing
were identified by varying the number of impeller blades. Noise reduction measures were proposed by analyzing the noise characteristics of the suction housing with respect to the excitation frequency for the different numbers of impeller blades modeled. The proposed measures avoided resonance in the suction housing by
reducing the BPF through reduction of the number of impeller blades. The effects of the blade number upon the noise characteristics and performance of the suction housing were investigated. The acoustic characteristics of the suction housing interior were analyzed using BEM. A noise reduction measure was proposed by analyzing
the characteristics of the different FRFs resulting from the use of different numbers of impeller blades. A key analysis informing the proposed noise reduction measure was an inner field analysis conducted using various excitation sources.