A New 3-D Sound Intensity Measurement System for Airborne Sound Insulation of Building Elements

In green building design, sound insulation of building elements is an important means to improve the indoor acoustic environment. However, there is still a lack of study on the measuring sound transmission loss by 3-D sound intensity method. In this study, a new 3-D sound intensity measurement system is used to calculate the sound intensity vector and estimate sound insulation property of the building element. The results of the numerical simulation indicate that the magnitude bias which meet accuracy requirements are less than 2dB within the range between 0Hz and 2kHz. In terms of directional bias ,it is close to 4° when f=2kHz for the 3-D probe. In order to validate the performance of the system further, the data measured by 3-D sound intensity measurement system is compared to the one measured using the pressure method and 1-D sound intensity method in building sound acoustic insulation lab. The experimental results demonstrate that the 3-D sound intensity measurement system can be used to calculate the sound transmission loss as well as describing the acoustic defect of the building elements, and it is suitable for the field measurement.