PRE-REDUCING THE INTERMITTENT EXHAUST NOISE BY OPTIMIZING THE EXHAUST PIPELINE AT THE DESIGN STAGE

摘要

The method for pre-reducing the intermittence exhaust noise (IEN) by optimizing the exhaust pipeline at the design stage is proposed. Traditionally, the noise in pneumatic factional clutch and pneumatic frictional brake (PFC/B) is reduced on the condition of the cylinder and pipeline already both designed and fixed. So the pre-reduction of IEN by optimizing the pipeline can relieve the effort for de-noise by using mufflers. Firstly, this paper adopts the electrical transmission line method to deduce the frequency response function (FRF) of the pipeline. Then the linear predication is used to analyze the FRF. Finally, an optimization method is employed to search the optimum parameters of pipeline. The verified experiment results indicate that the proposed method effectively pre-reduce IEN by 5.0 dB especially 5.8 dB below the high-frequencies from 2 kHz to 16 kHz on the 1/1 octave spectrum.