rotary compressor, discharge muffler, transmission loss
The discharge muffler of the rotary compressor is used to reduce the discharge noise produced by pressure pulsations. In order to obtain the transmission loss of discharge muffler, four microphone experimental devices used to measure the transmission loss of the muffler is established. The device is based on the transfer function method on the assumption that there is only plane wave in the tube, thus the measurement range of the device is discussed at the same time. Then the transmission loss of a contraction chamber is measured and calculated theoretically and the validity of the experimental device is verified through comparing the measurement and theoretical result. At last, a few various mufflers are measured using the experimental device and simulated by finite element method (FEM). The transmission loss of mufflers in the air is obtained and the experimental and simulation results are verified by each other.