Suction Pulsations and Flow-induced Noise in Reciprocating Compressors

摘要

This investigation demonstrates that the upstream flow relative to the suction valve can have a significant influence on the noise emitted during the suction process. Specifically, a noise problem on a customer appliance was detected in the 1 kHz 1/3-octave band. The excitation mechanism of the appliance was caused by suction pulsations. The compressor shell itself did not radiate any notable noise in that band, which is mainly due to the fact, that the muffler has a direct suction admission via a flexible telescope. The unexpected noise source appeared when changing the design of the muffler outlet tube, which connects the muffler volume with the suction port. The noise phenomenon is investigated theoretically and experimentally, and a new muffler design with improved acoustical properties is proposed.