Performance Calculation And Analysis Of Sound Transmission For Double Panel Structure

Double panel structure has widespread application in modern engineering. In many fields such as navigation and aviation, lots of noise transmits through this structure and it is used to increase the transmission loss. In applied acoustics, good sound transmission performance is demanded in many areas. Therefore, double panel structure has great significance in acoustics technology, and it is valuable to analyze its sound transmission performance.In fact, the problem of sound transmission of double panel structure is complex. Sound wave has both reflection and transmission at the interface. When the sound wave transmits through solid, there will be pressure wave like through liquid as well as shear wave. In this paper, first of all, when the angle of incidence isn't large and the thickness is much less than length and width, it can be considered as that the panel has plane longitudinal wave only without transverse wave. Then it can be studied as the problem of sound transmission through liquid. The transmission coefficient formula of infinite-double panel structure is derived and the transmission coefficient of double panel structure is calculated.Then adopt the empirical formula method including transverse wave and the transmission coefficient formula of finite-double panel structure with all-around constraint is deduced. The transmission performance of three models is compared and analyzed.After calculating and analyzing, the conclusion is received: in analysis frequency channel ,the larger space between two panel, the more thinner thickness of panels and the more smaller incidence angle of sound wave(0 is vertical incidence),then the better sound transmission performance. Among three models, the finite-double panel structure with all-around constraint considering the infection of all-around constraint has the smallest sound transmission performance. But it is the best one in accord with the actual structure. Finally, the visualization of calculation of sound transmission coefficient in three models is realized with the help of GUI of MATLAB, which simplifies the calculation of sound transmission performance of actual structure, provides an evidence for optimizing structural sound transmission performance in a short time, and realizing the application in engineering.