Study On The Acoustics Performance Of Porous Metal Material Under High Temperatures And The Design Of A Testing System

Due to the attractive potential application values of porous metal material in the aviation industry, deep sea engineering and other important areas, there search of the properties of porous metal material becomes more and more important, the research on its sound absorption performance have also been more and more attention. In this paper, based on the basic theory of the summary and analysis, the acoustic properties of porous metallic materials were studied by numerical simulation method, at the same time to design and build the porous metal material heat acoustic performance testing device, also has carried on the preliminary experiment research.By means of acoustic wave propagation theory to summarize, the concrete analysis of the circular tube of plane wave propagation, circular tube acoustic transmission attenuation, and the influence of circular tube temperature on the acoustic wave propagation, using COMSOL MULTIPHYSICS software simulation of the circular tube with different temperature field acoustic propagation situation, summarizes the circular tube temperature on the influence law of acoustic wave propagation.Based on the research of the porous sound absorption theory model, compares all kinds of models of summary. At the same time introduces the dual microphone the basic principle of transfer function method, this paper discusses the dual microphone transfer function method to adapt to high temperature in porous materials acoustic tests.Using COMSOL MULTIPHYSICS software, a transfer function method is introduced, and different materials of porous metal material thickness, different air back layer thickness, sound absorption performance under the condition of different combination of numerical.analysis, and under the action of the different temperature field of porous metal materials carried on the thorough analysis. Found with the combination of the air interlayer simulated porous sound absorbing material has good acoustic performance.Based on double microphone transfer function method, on the basis of design to build the porous metal material heat acoustic performance testing device, the design of specific analysis of the influence of some factors on the test equipment, and has carried on the preliminary experiment research.The work in this thesis is supported by the Project of National Natural Science Foundation of China(Grant No.51365046).