• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Ultrasonics, Ferroelectrics and Frequency Control, IEEE Transactions on >Damage characterization using guided- wave linear arrays and image compounding techniques
【24h】

Damage characterization using guided- wave linear arrays and image compounding techniques

机译：使用导波线性阵列和图像合成技术进​​行损伤表征

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

In this work, a high-resolution imaging method for the inspection of isotropic plate-like structures using linear arrays and Lamb waves is proposed. The evaluation of these components is limited by the low dynamic range resulting from main lobe and side lobe field patterns, and from the narrowband nature of the Lamb waves. Based on a full matrix array, synthetic aperture technique using all emitter-receiver combinations, different images from the same object are obtained by using different apodization coefficients, which are related to a trade-off between main lobe width and relative side lobe level. Several image compounding strategies have been tested and a new algorithm, based on apodization and polarity diversities between signals, is proposed. However, some effects, such as the dead zone close to the array and reverberations caused by interactions of the wavefront and defects, still limit the quality of the images. The use of spatial diversity, obtained by an additional array, introduces complementary information about the defects and improves the results of the proposed algorithm, producing high-resolution, high-contrast images. Experimental results are shown for a 1-mm-thick isotropic aluminum plate with artificial defects using linear arrays formed by 30 piezoelectric elements, with the low dispersion symmetric mode S0 at the frequency of 330 kHz.
机译：在这项工作中，提出了一种用于利用线性阵列和兰姆波检查各向同性板状结构的高分辨率成像方法。这些分量的评估受到主瓣和旁瓣场模式以及兰姆波的窄带特性所导致的低动态范围的限制。基于全矩阵阵列，使用所有发射器-接收器组合的合成孔径技术，可以通过使用不同的切趾系数来获得来自同一物体的不同图像，这些切趾系数与主瓣宽度和相对旁瓣水平之间的权衡有关。测试了几种图像合成策略，并提出了一种基于变迹和信号之间极性差异的新算法。但是，某些影响，例如靠近阵列的盲区和由波前和缺陷的相互作用引起的混响，仍然限制了图像的质量。通过附加阵列获得的空间分集的使用引入了有关缺陷的补充信息，并改善了所提出算法的结果，从而生成了高分辨率，高对比度的图像。实验结果显示了使用由30个压电元件形成的线性阵列，厚度为1毫米的具有人工缺陷的各向同性铝板，在330 kHz的频率下具有低色散对称模式S0。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号