Acoustical Parameters of Porous Materials and Their Measurement
نویسندگان
چکیده
Acoustical parameters of porous materials give the necessary and important information for noise control engineers. Profound knowledge their physical characteristics enable an effective sound absorber material design. The theory of sound-absorbing materials has progressed considerably during the last decade. A noise control engineer with serious interest in sound absorbing technology is advised to study all this parameters. Noise control engineers frequently face problems of design sound absorbing materials that provide the desirable sound absorption coefficient that minimizes the size and cost, does not introduce any environmental hazards, and stands up to hostile environments. The designers of those absorbers must know how to choose the proper material, its geometry and the protective facing. Porous sound-absorbing materials are utilized in almost every areas of noise control engineering. This paper deals with the acoustical parameters of porous materials and their measurement.
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