Design and simulation optimization of a new impedance composite muffler

Mufflers are widely used to control pipeline noise in ventilation engineering. Substation noise belongs to low frequency noise, and the low frequency muffler effect is required to be higher. In this paper, a new structure of composite impedance muffler is proposed, and the sound field and flow field inside the muffler are simulated by COMSOL Multiphysics finite element method. The pressure loss and insertion loss of different structure mufflers are studied and analyzed, and a new impedance compound type of ventilation pipe muffler is designed and optimized, which can provide reference for substation muffler design and engineering application. The results show that the new impedance composite muffler has good muffling effect in low, medium and high frequencies; the muffling effect is better in $0 \sim 500 \mathrm{~Hz}$, and it is better than other types of mufflers by about 150%.