ELASTIC MODEL FOR SIMULATING ULTRASONIC INSPECTION OF SMOOTH AND ROUGH DEFECTS
ELASTIC MODEL FOR SIMULATING ULTRASONIC INSPECTION OF SMOOTH AND ROUGH DEFECTS
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DOI：
10.1016/0041-624x(91)90080-r
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发表时间：
1991-11-01
期刊：
影响因子：
4.2
通讯作者：
CULVERWELL, ID
中科院分区：
文献类型：
--
作者：
OGILVY, JA;CULVERWELL, ID
本文提出了一种光滑和随机粗糙缺陷对超声波散射的模型。该模型采用基尔霍夫理论，是弹性的，这样，模式之间的转换压缩和剪切波包括在制定。该模型的目的是模拟超声波无损检测的情况下，通过指定的位置和方向的缺陷内的各向同性材料，连同检测表面上的发射器和接收器的位置。单色波和脉冲的散射的结果。它示出了如何小的粗糙度水平可以影响回声动力学曲线和衍射信号如何可能会失去由于散射从粗糙的表面缺陷。研究还表明，当存在粗糙度时，所有三种模式的波之间耦合的通常规则不再成立。特别是，粗糙度导致水平偏振剪切波（SH）和其他两种波模式之间的耦合。模型的预测也与早期的声学模型进行了比较，表明模式转换效应的重要性，当考虑粗糙的缺陷嵌入固体。
A model is presented for the scattering of ultrasonic waves from smooth and randomly rough defects. The model uses Kirchhoff theory and is elastic, such that mode-conversion between compressional and shear waves is included in the formulation. The model is designed to simulate ultrasonic non-destructive testing situations, by specifying the location and orientation of a defect within an isotropic material, together with transmitter and receiver locations on an inspection surface. Results are presented for the scattering of both monochromatic waves and of pulses. It is shown how small levels of roughness can affect echodynamic curves and how diffracted signals may become lost due to scatter from the rough faces of defects. It is also shown that the usual rules for coupling between waves of all three modes no longer hold when roughness is present. In particular, roughness leads to coupling between horizontally polarized shear (SH) waves and the other two wave modes. The model predictions are also compared with an earlier acoustic model, indicating the importance of mode-conversion effects when considering rough defects embedded within solids.