Noise Characteristics Determination of Vehicle Air-Condition Compressor 2009-01-1861

Vehicle dominating sound sources (like the combustion engine and the power-train) have been significantly improved in terms of sound emission during the last decades. Therefore, the acoustic performance of air-condition (A/C) compressors become more important for passenger comfort. At engine idling and at extreme temperatures the A/C-compressor can be audible as the significant sound source. However, the aim of this paper is to quantify air-borne noise characteristics of vehicle air-condition compressor. A small reverberation chamber was designed and acoustic characteristics of the sound field inside the chamber were determined. Objective evaluation of the air-borne sound emission of a compressor was performed. The results indicate that the air-borne noise in terms of sound pressure level (SPL) is increased as the increase of speed and charge load. Furthermore the SPL changed from microphone position to another, where the right hand position (point No. 3) is highest level than that for the other points.