Optimization design of composite microperforated tube muffler for diaphragm air pump

According to the spectrum characteristics of exhaust noise of a diaphragm pump, an efficient broadband series-parallel composite microperforated tube muffler is proposed. A numerical model for the transmission loss of composite microperforated tube muffler is derived. Based on this model, the average transmission loss of composite microperforated tube muffler is optimized by using Isight software integrated with Actran and Matlab software, and a variety of group genetic algorithms are used to widen the frequency band of muffling and improve the performance of muffling. The test results of the optimized muffler show that the exhaust noise of the diaphragm pump decreases obviously in the whole frequency band, the total sound pressure level is decreased by 10 dB(A), and the maximum noise reduction is 22 dB(A) in the most concerned frequency band of 1 000~5 000 Hz. The experimental results show that the composite microperforated tube muffler and its optimal design program provide an efficient and feasible method for broadband noise control.