通过对双层厚壁圆筒周向导波的频散现象的研究,以及与单层圆筒周向导波特性的比较,发现周向导波在双层厚壁圆筒中传播时,会发生明显的频散现象和模态干涉现象,其第1阶模态在高频时接近于无频散R ay le igh面波。在其高阶模态上,层间效...通过对双层厚壁圆筒周向导波的频散现象的研究,以及与单层圆筒周向导波特性的比较,发现周向导波在双层厚壁圆筒中传播时,会发生明显的频散现象和模态干涉现象,其第1阶模态在高频时接近于无频散R ay le igh面波。在其高阶模态上,层间效应被弱化,因此,应将层间界面裂纹无损检测的频率激发范围,集中于低阶模态频率上。研究发现,第2阶模态,具有在层间界面上集中能量的特点,因此,可用于层间界面裂纹的周向导波无损检测技术中。展开更多
We report two models of the lateral displacement of acoustic-wave scattering on a fluid-solid interface that reveal an acoustic analog of the Goos-Hainchen effect in optics. This acoustic analog is called the acoustic...We report two models of the lateral displacement of acoustic-wave scattering on a fluid-solid interface that reveal an acoustic analog of the Goos-Hainchen effect in optics. This acoustic analog is called the acoustic Goos-Hainchen effect. Using newly proposed models, we made numerical calculations for the system ofa water-Perspex interface. Specifically, in the post-critical-angle region, we observed a lateral displacement （and transition time） of the reflected P-wave with respect to the incident P-wave. The first arrival of the acoustic signal from the interface is found to be a reflected P-wave rather than the sliding-refraction P-wave usually described in traditional acoustic-logging sliding P-wave theory. For both proposed models, the effective propagation speed of the reflected P-wave along the interface depends on not only the physical properties of the interracial media but also the incident angle. These observations are intriguing and warrant further investigation.展开更多
文摘通过对双层厚壁圆筒周向导波的频散现象的研究,以及与单层圆筒周向导波特性的比较,发现周向导波在双层厚壁圆筒中传播时,会发生明显的频散现象和模态干涉现象,其第1阶模态在高频时接近于无频散R ay le igh面波。在其高阶模态上,层间效应被弱化,因此,应将层间界面裂纹无损检测的频率激发范围,集中于低阶模态频率上。研究发现,第2阶模态,具有在层间界面上集中能量的特点,因此,可用于层间界面裂纹的周向导波无损检测技术中。
基金the Xi’an University of Posts and Telecommunicationsthe Physical Sciences Division at the University of Chicagothe Scientific Research Program(Grant No.15JK1685)of the Shaanxi Provincial Education Department
文摘We report two models of the lateral displacement of acoustic-wave scattering on a fluid-solid interface that reveal an acoustic analog of the Goos-Hainchen effect in optics. This acoustic analog is called the acoustic Goos-Hainchen effect. Using newly proposed models, we made numerical calculations for the system ofa water-Perspex interface. Specifically, in the post-critical-angle region, we observed a lateral displacement （and transition time） of the reflected P-wave with respect to the incident P-wave. The first arrival of the acoustic signal from the interface is found to be a reflected P-wave rather than the sliding-refraction P-wave usually described in traditional acoustic-logging sliding P-wave theory. For both proposed models, the effective propagation speed of the reflected P-wave along the interface depends on not only the physical properties of the interracial media but also the incident angle. These observations are intriguing and warrant further investigation.
