Research On Measure For Acoustic Parameters Of Damping Materials

Presently, modern high-technology has been developed rapidly, like aviation, navigationand spaceflight etc. But in this progress, noise has become one of the most severe pollutionsin our society. Therefore, reducing noise become important to modern projects, no matter forcivilian or army. As a member of material for noise reducing, macromolecule dampingmaterial has attracted more and more attention and the research of acoustic parametersbecome the most pressing problem.A lot of measurement methods for acoustic parameters of damp material exist, but it isfaulty to measure the acoustic parameters of damp material with low Young’s modulus. Theprimary content of this article is the research of measurement system and methods foracoustic parameters of damping material with low Young’s modulus. Based on the theory ofcurving vibration of rods, the curving vibration of beams composed with still beams anddamping materials is researched, the relationship between the amplitude distribution andacoustic parameters of the composite beam curving vibration is deduced. Then, obtainacoustic parameters of the composite beam and damping material by fitting the curve of thetheory relationship with the measured amplitude distribution. The measurement error of theamplitude distribution curve fitting method is researched by theory model and emulationcalculation. The adaptability of this method is testified by sympathetic vibration method. Bythe experiment date analysis, it is found that the acoustic parameters inversion by amplitudedistribution curve fitting method accord with the measured date by sympathetic vibrationmethod and this method can be used to measure the acoustic parameters of damp materialwith low Young’s modulus.