Reduction of Micro-Pressure Wave by Active Control of Propagating Compression Wave in High Speed Train Tunnel

摘要

For the improvement of the sound environment around a portal of a high speed train tunnel, model experiments for the reduction of MPW (Micro-Pressure Wave) have been studied. In order to reduce the level of MPW, a control wave, that is a positive pressure, is generated at a side-branch in a model tunnel and is superposed on the incident wave front of a compression wave propagating through the tunnel. The method of active reduction of MPW and experimental equipment are shown. Characteristics of the wave forms of the compression wave and the control wave with suitably designed servo actuators were examined. The experimental results of the reduced level of MPW agreed well with numerical calculation results.