被孔隙介质约束的弹性杆中的导波  

Guided waves in a solid rod surrounded by porous media

作　　者：童紫薇 韩庆邦[1] 姜学平[1] 张雨[1] 齐立华[1] 朱昌平[1] TONG Ziwei;HAN Qingbang;JIANG Xueping;ZHANG Yu;QI Lihua;ZHU Changping(College of IOT Engineering of Hohai University, Changzhou 213022, China)

机构地区：[1]河海大学物联网工程学院,常州213022

出　　处：《应用声学》2016年第5期384-394,共11页Journal of Applied Acoustics

基　　金：国家自然科学基金(11274091;11574072;11274092);河海大学中央高校基金项目(2011B11014)

摘　　要：为了研究导波在被孔隙介质约束的弹性杆结构中的传播规律,分析孔隙参数对导波传播特性的影响,本文建立了无限大孔隙介质包裹圆柱体的理论模型,利用孔隙介质弹性波动理论,分析了导波的频散曲线,以及圆柱半径和孔隙参数对于导波传播特性的影响。结果表明,在该结构中传播的纵向导波存在频散特性。内部圆柱半径的改变影响波导结构,从而影响导波传播。外部孔隙介质的渗透率对于导波频散的影响较小,孔隙度的改变影响孔隙介质体波波速,从而影响导波频散曲线的截止频率。同时,导波存在较小的衰减,且衰减随孔隙度增大而增大。这些结果对于后续开展无限大介质包裹弹性杆结构的超声无损评价提供了一定的理论参考。To derivate the propagation characteristics of guided waves in a solid rod surrounded by porousmedia and analyze the effects of the porous media parameters to the dispersion characteristic, a model ofsolid rod surrounded by porous media is built. Based on the elastic-dynamic theory of liquid-saturated poroussolid and numerical computation, the dispersion characteristic of guided waves in this structure with differentcylinder radius and porous medium parameters are discussed. Results show that the longitudinal guided wavepropagation in this structure is dispersive and influenced by the radius of the rod and porosity of the porousmedium. The porosity has a certain effect on the dispersion and attenuation characteristic, which can providea theoretical reference for the non-destructive evaluation to the structure of a solid rod surrounded by infinitemedia.

关 键 词：导波 孔隙介质 频散特性 

分 类 号：O426.2[理学—声学]