Application of impedance complex muffler in noise control of mine ventilation shaft

The air flow volume of mine fan is big, the noise from the diffusion outlet of ventilation shaft is intense, and has a wide frequency range, so it is difficult to be controlled. According to the frequency characteristics of the expansion chamber muffler and the disadvantage of existing through frequency, the structure was improved and combined with absorptive muffler, a new type of impedance composite muffler was designed. Its noise attenuation is larger in the frequency range of 63-4000 Hz, and the resistance loss is small, moreover, the design is easy and the design theory is reliable.