低频声音通过气固界面的传输。

Low-frequency sound transmission through a gas-solid interface.

机构信息

Earth System Research Laboratory, Physical Sciences Division, Cooperative Institute for Research in Environmental Sciences, University of Colorado and National Oceanic and Atmospheric Administration, Mail Code R/PSD, 325 Broadway, Boulder, Colorado 80305-3328, USA.

出版信息

J Acoust Soc Am. 2011 Feb;129(2):EL45-51. doi: 10.1121/1.3535578.

DOI:10.1121/1.3535578

PMID:21361411

Abstract

Sound transmission through gas-solid interfaces is usually very weak because of the large contrast in wave impedances at the interface. Here, it is shown that diffraction effects can lead to a dramatic increase in the transparency of gas-solid interfaces at low frequencies, resulting in the bulk of energy emitted by compact sources within a solid being radiated into a gas. The anomalous transparency is made possible by power fluxes in evanescent body waves and by excitation of interface waves. Sound transmission into gas is found to be highly sensitive to absorption of elastic waves within a solid.

摘要

声波在气固界面的传输通常非常弱，因为界面处的波阻抗存在巨大差异。本文研究表明，在低频下，衍射效应会导致气固界面的透明度显著增加，从而使固体中紧凑型声源发出的大部分能量辐射到气体中。反常的透明度是由渐逝体波中的功率流和界面波的激发所实现的。研究还发现，声波传入气体中对固体中弹性波的吸收非常敏感。