Study And Simulation Of Wooden Perforated Panels Structure's Sound Absorption Performance

Medium density fiberboard (MDF) has been widely used due to the peculiarities of higher static load strength, dimensional stability, good watertight capacity and so on. Wooden perforated panel absorption structure with MDF as basis material just suits the tendency of no fibrosis absorption material. This thesis regards wooden perforated panel absorption structure with MDF as the research object to find out the laws of the structure sound absorption, and to provide the foundation of methodology and technique support for developing advanced sound absorption construction.The paper mainly adopts the methods of testing and simulation by means of wood science, architectural acoustics, finite-element theory and statistics in multi-subjects area to guarantee widespread of the research foundation and reliability of research results.Sound absorption coefficient of perforated panel structure under different absorption structure conditions is measured by means of standing wave tube test, Furthermore, it introduces statistics software SPSS to analyze the correlation of each influential factor of absorption performance. In order to verify wooden perforated panel's influence to sound field, it simulates the distribution of SPL and T30of one building with certain type perforated sound absorption construction on the given surfaces by the use of sound field simulation software ODEON. The simulation results confirm tone quality improvement and noise control function of the certain type wooden perforated panel.It can get the following absorption laws through standing wave tube experiment. The structure's high frequency absorption property is improved with the bore diameter decreasing. Perforation rate is the main factor which affects the structure's high frequency sound absorption performance. Panel thickness mainly affects sound absorption structure's high frequency performance. Resonant frequency moves slightly to the low-frequency with the increasing of panel thickness. With the cavity depth increasing, the low frequency sound absorption performance of the structure is enhanced. When cavity depth exists, small perforation rate absorption performance is good in the low frequency range, but the bigger the perforation rate is, absorption performance is better in the high frequency range. Hole shape has little impact on the sound absorption performance, so the round hole is the best choice for its good manufaturability and the convenience of sweeping. Whether the hole non-uniformly arranged a beautiful pattern or uniformly distributed, two pieces of perforated panels with the exactly same panel thickness and perforation situation is follow the same sound absorption rule. Having decorative facing or not has a little effect on absorption property, so MDF which used for manufacturing perforated panel can be coated with decorative facing in order to get the best acoustics and decoration effect in general.To make the designers forecast the laws of the sound performance of sound absorption construction in the beginning, it is an inexorable trend of developing computer simulation technology. Therefore, on the basis of standing wave tube method, this paper adopts finite element method to study the absorption performance of wooden perforated panel. The jobs include modeling, meshing, loads, solution and results. The results of the finite-element method show that the effect of application of the finite-element analysis software ANSYS to wooden sound structure absorption performance analysis is obvious. There are some sound pressure distribution zones with peak and valley alternations between the sound source and the tested material. It coincides with the results of the test which is done by the standing wave tube equipment. The result changes accordingly with structure parameters and the sound source frequency varying. Simulation and standing wave tube method have the same trend of absorption coefficient curve distribution. The maximum error is6.73%and the minimal error is3.11%of3analytical examples through error analysis. It testifies the method's feasibility and finite-element model's reliability. It shows that wooden perforated panel absorption performance is studied by finite-element method can meet the accuracy requirements.