Mechanical Impact Noise Analysis of Rotary Compressor

摘要

In the noise and vibration test of 8HP rotary compressor, the peak value of noise and vibration is especially high at frequency range between 600～1000Hz. The sound pressure level (SPL) exceeds the enterprise criterions and the sound quality is so tough that persons cannot bear such annoying noise. Two experiments, pressure pulsation above/below compressor motor and mechanical impacts of compressor pump-rotor unit, are particularly carried out in order to identify the noise sources. The test results confirm that the axial up-down movement of pump-rotor unit is the primary reason, causing the abnormal noise and vibration. Several measures, including partially cutting the circumferential edge of the stator and increase the height differential between rotor and stator, have been taken in order to reduce pressure pulsation above/below motor and restrain the axial movement of shaft-rotor unit. With these measures, the noise problem of 8HP rotary compressor has been solved successfully. Finally the sound pressure level decreases about 4dB and the sound quality is comfortable and good to hear.