An effective experimental method for identifying radiated noise of different angular ranges for the rolling-piston compressor

Abstract

In the traditional analysis method of noise signals, it is very difficult to relate the overall noise from compressors to the angular position. The experimental method of separating the overall noise of different angular ranges is carried out at the real conditions. The starting position of the rotary piston is labelled with vane displacement and the test signals are synchronously sampled. Experimental results are analysed through fast Fourier transform method based on different angular ranges, which displays the following useful conclusions. The experiment technology could effectively identify the angular ranges for the frequency bands with prominent noise level; for the experimental rolling-piston compressor, the vibration, and sound pressure level of the discharge process (210–360 angular degrees) are the largest above the frequency 500 Hz. The discharge process is divided into three parts, where the final part contributes a little to the overall noise level when compared with the other two stages. Pressure pulsation is an important source of vibration and noise and its suppression of peak frequencies is the key of low-noise design of the compressor.