並列摘要
In this study, a typical device with serious intake noise induced by a high speed fan was considered. The high-frequency components were treated by using 1 cm thick foam absorber in consideration of the size limitation of the equipment. The low-frequency noise components of 630 Hz, 800 Hz and 1,250 Hz were suppressed by using an expansion chamber muffler with extended tubes to enable broadband silencing. From the actual spectral measurements, optimal placement of the transmission loss peaks was realized to effectively suppress the low frequency noise, which was difficult to eliminate in practice. The original noise of the equipment was 80.5 dB(A), which was reduced to 70.5 dB(A) after installation of the silencer, achieving a significant 10 dB(A) reduction. The flow rate of the air supply was only slightly reduced and the original equipment performance was not impaired.