The Computer Simulation Analysis Of Micro Perforated Panel Absorbers And Parallel Structures

When we decorate a cinema, theater, or a multifunctional-hall, it is absolutely necessary to use sound absorption materials in controlling the reverberation time, reducing noise, improving sound proliferation and eliminating acoustic flaw. Sound absorption materials play an extremely important role in improving acoustic and reducing noise. Different kinds of sound absorption materials have different sound absorption characteristics, so how to use these sound absorption materials correctly will affect the final acoustic quality. In the acoustical design of modern construction, the sound absorption materials must not only have the best sound absorption properties but also the beautiful decoration effects and various construction properties in the decoration design: fire prevention, moisture resistance, solidity, heat preservation and so on. Nowadays micro perforated panel is a kind of structure widely used in areas of sound- absorption and sound- elimination.First, on the basis of reading many sound absorption theories, this thesis introduces Dah You Maa's theory of micro perforated panel absorbers, and uses numerical processing capability and the graphical visualization characteristic of MATLAB software to study some factors which affect the characteristics of micro perforated panel absorbers, such as cavity depth, perforated rate, plate thickness and perforation diameter.Second, in order to enhance effects of micro perforated panel absorbers, this thesis also summarizes a lot of micro perforated panels absorber structures including double micro perforated panel,different perforated rate's micro perforated panel and so on. On the basis of heory, the paper uses the analogy method of sound-electricity equivalent circuit to build "parallel" model of different cavity depth micro perforated panel, calculates and analyses the acoustic impedance and sound absorption coefficient of micro perforated panel of different perforation diameter,perforated rate and plate thickness, draws frequency response curves of sound absorption coefficient, and gets the compendious sound absorbing results.At last, the paper cites the applications of micro perforated panel and the combined paralleled micro perforated panel.The research results can provide basic information of micro perforated panel absorbers for engineers and apply to acoustical design and noise control projects.