An experimental study on multiple staggered natural ventilation sound insulation windows for sound enclosures

Growing interest has been developed recently on designing acoustic ventilation windows with both sound insulation and air ventilation. One important design for preventing traffic noise into rooms is staggering opening sashes of a spaced double glazing window to allow ventilation. In this paper, a multiple staggered natural ventilation sound insulation window is proposed for sound enclosures that are used to reduce the sound radiation to outside from a noise source inside. The enclosure used in the experiments is 0.70 m long, 0.52 m wide, and 0.56 m high, and a loudspeaker installed inside the enclosure is used as the noise source. The proposed window consisting of multiple staggered glasses is installed on the opening of the enclosure, and the sound pressure levels measured outside the enclosure are used to evaluate the performance of the window. The experiment results show that increasing length and number of the glasses improves the noise reduction performance of the window, and the noise reduction with 3 glasses can be up to 10.7 dB comparing that of the opened enclosure. Although it is still much smaller than the 22.0 dB noise reduction of the closed enclosure, the enclosure has nature ventilation with the proposed window.