Based on the spectral characteristics obtained from actual field noise source tests of various industrial fans, determine the required noise reduction levels in specific frequency ranges for designing acoustic absorbers and fluid channels. Additionally, a narrow rectangular channel with a large acoustic material surface has been employed to enhance absorption. Furthermore, at high noise levels, the noise sources of the fans often have more than one spectral value, and the noise reduction requirements vary for different frequency bands.

These silencers for the ventilation管道 and exhaust fans of this series are of impedance type, employing resistive structures that absorb and suppress high and mid-frequency noises, as well as resistive structures that suppress and reduce mid and low-frequency noises. Additionally, the resistive channels feature both high and low-frequency sound-absorbing and noise-suppressing zones, broadening the noise-suppression frequency range to the maximum, achieving excellent noise reduction performance.