Reduction of Impulsive Noise Caused by Unsteady Compression Wave

When an unsteady compression wave propagating in a tube arrives at its exit, an impulsive wave is emitted toward the surrounding, which causes an impulsive noise. The objective of this work is to investigate the appropriate silencer configuration for reducing this impulsive noise. Five kinds of silencers were installed at a shock tube exit, and their effects on the impulsive noise were investigated numerically and experimentally. Two-dimensional unsteady conservation equations were solved by means of a PLM. Experiments were carried out using a shock tube with an open end. As a result, the effect of silencer configuration on noise reduction was clarified, and it was found that a suitable choice of the silencer could reduce the strength of the impulsive wave by about 25%.