A STUDY OF THE SOUND REFLECTION FROM POROUS MATERIAL BY IMPULSE METHOD

来源 :Chinese Journal of Acoustics | 被引量 : 0次 | 上传用户:brianwang1982
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This paper presents a study of the reflection of sound pulse from porous material when the im-pulse sound source and receiver are located on a line perpendicular to the surface of the material.The transfer functions of reflected sound waves were calculated from the experimental incident and thereflected sound pulses by use of DFT.The impulse response of reflected sound waves can be calculatedtheoretically under the assumption of idealized porous material.Both local reacting and extendedreacting materials were taken into account in the calculations. comparison of the calculationsfor spherical waves and plane waves provides a measure of the effect of spherical waves on thetransfer function of reflected sound waves.For a layer of porous material the reflections in thematerial are studied. This paper presents a study of the reflection of sound pulse from porous material when the im-pulse sound source and receiver are located on a line perpendicular to the surface of the material. Transfer functions of reflected sound waves were calculated from the experimental incident and thereflected sound pulses by use of DFT. impulse response of reflected sound waves can be calculated the undertically under the assumption of idealized porous material.Both local reacting and extended reactance materials were taken into account in the calculations. comparison of the calculations for spherical waves and plane waves provides a measure of the effect of spherical waves on thetransfer function of reflected sound waves. For a layer of porous material the reflections in thematerial are studied.
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