Experimental measurement method for medium-high frequency acoustic performance of large-pipe-diameter silencer

Abstract

The invention provides an experimental measurement method for medium-high frequency acoustic performance of a large-pipe-diameter silencer. According to the experimental measurement method for the medium-high frequency acoustic performance of the large-pipe-diameter silencer, due to the fact that a hollow pipeline and a tail end silencer are arranged at the tail end of an experimental facility, wherein the hollow pipeline and the tail end silencer have different impedances, the boundary conditions can be changed, and an equation set representing the relation between the amplitude value of a front incident acoustic wave and the amplitude value of a front reflection acoustic wave of the silencer to be tested and an equation set representing the relation between the amplitude value of a rear incident acoustic wave and the amplitude value of a rear reflection acoustic wave of the silencer to be tested are set up. On the basis of the existing silencer transmission loss measurement principle and the experimental facility, an inlet-and-outlet measurement pipe section which is composed of two rigid concentric round pipes is designed, and due to the fact that the plane wave cut-off frequency of the annular pipe structure and the plane wave cut-off frequency of the inner pipe with the smaller diameter of the inlet-and-outlet measurement pipe section are much larger than the plane wave cut-off frequency of an inlet-and-outlet pipeline of an existing silencer, the measurement frequency range of the transmission loss of the large-pipe-diameter silencer is expanded. According to the experimental measurement method for the medium-high frequency acoustic performance of the large-pipe-diameter silencer, a non-reflection end does not need to be designed, and the medium-high frequency acoustic characteristics of the large-pipe-diameter silencer can be accurately measured.

Description

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AI Technical Summary

Benefits of technology

This technology doesn't require any special parts like an echo sounder or microphone attached on top of it for measuring its properties during low frequency sounds better compared with traditional methods such as ultrasonics.

Problems solved by technology

This patented technical solution describes how reducing noise from an inside-combusted engine's pipe systems improves its overall quality by optimizing the design of the inner part or components used therein without affecting their function effectively during operation.

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