Virtual experimental study on sound prediction in multiple connected spaces by surface coupling approach

Plenum window has attracted a lot of attention in the past decades, since it simultaneously allows noise reduction and natural ventilation. Many researches have been focused on the investigation of its acoustical benefits over conventional windows by means of laboratory experiments. Using the Surface Coupling approach, the paper will predict the sound transmission through a plenum window connecting a room with noise sources and a semi-free space. In this way the noise reduction performance of the window could be further studied analytically. Based on the coupling approach, the entire acoustical system can be divided into three distinct sub spaces: the room, the plenum window and the semi-free space. Each subspace can be characterized by two descriptors defined across virtual coupling surfaces interfacing these spaces: blocked pressure and surface impedance. The blocked pressure is the sound pressure response across the blocked coupling interface surface due to the operating noise sources. The surface impedance is the impedance of the coupling interface surface when the noise sources are off. The two descriptors will be identified in the paper by virtual experiments in order to find out whether the sound transmission in the entire system could be predicted using the experimentally identified subspace data.