水平剪切波在板表面附着物厚度检测中的应用研究.pdfVIP

第 xx 卷第 x 期 机 械 工 程 学 报 Vol.xx No.x 20xx 年 x 月 JOURNAL OF MECHANICAL ENGINEERING xxx. 2 0 x x 水平剪切波在板表面附着物厚度检测中的 应用研究* 吴 斌 李 杨 郑 阳 何存富 (北京工业大学机械工程与应用电子技术学院 北京 100124) 摘要：针对板表面附着物厚度检测的问题，提出一种基于水平剪切(Shear horizontal，SH)波的检测方法，该方法利用 SH 波的 频散效应对板表面附着物厚度变化敏感的特性，实现对表面附着物的厚度进行无损检测。建立 SH 波在双层结构中的波动模 型，并求解出双层弹性介质中 SH 波的波动方程。针对工业中出现的水垢等多种附着物厚度检测实例，绘制 SH 波群速度随 附着物厚度变化的曲线，并进一步提出 SH 波检测板表面附着物厚度的具体实施方法。利用该检测方法，对钢板—石灰膏涂 层模拟的锅炉水垢试样进行了试验研究。结论表明，通过测定低频段和高频段的 SH0 模态的群速度，可以分别对较厚附着层 和薄厚度附着层的厚度进行检测。 关键词：水平剪切波 表面附着物 水垢厚度 积碳层厚度 中图分类号：TB553 Thickness Measurement of Surface Attachment on Plate with SH Wave WU Bin LI Yang ZHENG Yang HE Cunfu (College of Mechanical Engineering and Applied Electronics Technology, Beijing University of Technology, Beijing 100124) Abstract ：A technique based on shear horizontal(SH) wave for thickness measurement of surface attachment on plate is presented. This nondestructive method is implemented by using the relationship between SH wave dispersion variety and the thickness changing. Propagation of SH wave in bi-layer elastic structure is modeled and analyzed. Considering several conditions of surface attachment such as boiler scale, the dispersion curve of SH wave which varying with attachment thickness is tracked. A concrete implementation of the SH wave attachment thickness measurement is provided. The experimental study on boiler scale thickness detection is carried out with the Steel-CaCO3 bilayer specimen. The results show that the measurement of surface attachment thickness (including relative thick or thin attachment) with SH wave can be realized by measuring the group velocity of SH0 mode under low or high frequency.