NOISE AND VIBRATION STUDIES IN A CO_2 COMPRESSOR

摘要

Many publications have pointed out Carbon Dioxide (CO_2) as an environmental friendly refrigerant fluid aiming to reduce the level of CO_2 emissions from refrigerating appliances. The possibility of replacing HFCs by employing CO_2 compressors has been leading the refrigeration industry to a continuos research on all the related fields. Concerning CO_2 application, significant progress in terms of both energy performance and reliability have been made by the optimization of the reciprocating compressor to meet CO_2 design demands. From a broader perspective, this paper intends to assess the acoustical performance of an energy efficient, reliable CO_2 reciprocating compressor through the identification of the sources and transmission paths, associating them to the overall sound level of both the compressor itself and a representative refrigerating appliance. Advanced methods are applied including numerical analysis, operational deflection shape (ODS), and acoustical holography to investigate the potential of a brand new reciprocating compressor platform designed for CO_2 application . The methodology employed is presented and has its scope on identifying, quantifying and judging the sources of the noise, transmission paths, and respective influences in the final radiator acoustical performance. Preliminary results point to a very positive perspective for the acoustical performance of the CO_2 compressor investigated, showing similar sound level when comparing to current baseline.