Research On Acoustic Characteristics Of Large Coupling Spaces

In recent years, a large number of large public buildings have been built in China. The internal space of the buildings are beyond the traditional concept of large space, its acoustic features are quite different with traditional space. A lot of acoustic problems have appeared, such as long reverberation time, Echo and the focus, low language articulation, high background noise and difficult to communicat. How to create comfortable acoustic environment in large space, has become a vital research subject.This paper firstly analysis scale and the coupling form of large space represented by large traffic constructions built in recent years. Through comparison and analysis measured and simulated data way to verify the adaptability of the acoustic simulation software ODEON, The last simulation analysis change rule of large space coupled soundfield which is different scales and coupling forms using the ODEON simulation software.At first, this paper summarize research methods and the research object of coupling space combined with the literature. Research methods include finite element method, statistical acoustic method and geometric acoustic method. The objects of study mainly include the attenuation curve of sound pressure level and reverberation time(RT). Factors affecting the coupled acoustic field are space size, area size and position.The second, in combination with the typical examples of large transportation building, the shape of large space is given priority to with rectangle. Length is more than hundred meters, some space even up to 500 meters. The most common length is about 200 meters. Transverse dimensions are more than 50 meters. The most common length is about 100 meters; Space height is about 20 meters. The paper has identified the form of the large coupling space through the analysis of internal function space layout, thus finally concluded two kinds of large space with large space coupling form and three kinds of large space with small space coupling form.Based on the acoustic testing and simulation of Harbin west railway station, the paper verify accuracy of the ODEON software simulating large coupling space acoustics. Finally, the paper simulation different forms, spatial scales, coupling open area and absorption coefficient impact on the large coupling space. The existence of coupling space has a great impact to smaller space, and can reduce the reverberation time of space; When Large space and small space couple together, acoustic environment will be large impact between two space, On the contrary, when large space and large space couple together, acoustic environment will be small impact between two space, When the large space and small space couple together and coupling open area smaller than 25 m2, decay curve present the single slope. Reverberation time can reduce by increased absorption coefficient range 0.3 to 0.4.The research is only a preliminary research of the basic acoustic characteristics of the large coupling space. It does not include different acoustic conditions of the large space, the evaluation criteria and other factors on large spatial acoustic characteristics which needs further research.