摘要
对利用斜探头激励和接收高阶纵向模态进行了实验研究。通过Snell定理和超声导波的相速度频散曲线选择斜探头的入射角和激励频率,可以激励所需的高阶纵向模态。但随着模态阶次和激励频率的增加,对单一模态的控制也变得更加困难。同时,实验分析了激励斜探头个数对模态选取的影响,说明通过增加斜探头的个数来抑制弯曲模态是十分必要的。
The excitation and reception of higher order longitudinal modes are investigated experimentally. According to Snell＇s law and phase velocity dispersion curves, incident angles and excitation frequencies of angle beam probes are chosen, and then, the wanted subsequently higher order longitudinal modes are excited in pipes. However, it will become more difficult to control excited modes as the order and excitation frequency of longitudinal modes become higher. Furthermore, the influence of the number of excitation angle beam probes on mode choice is analyzed. Experimental results show that it is essential to suppress flexural modes by increasing the number of excitation angle beam probes.
出处
《工程力学》
EI
CSCD
北大核心
2009年第3期246-250,共5页
Engineering Mechanics
基金
国家自然科学基金项目(10772009)
北京市自然科学基金项目(2072003
8062008)
北京工业大学博士科研启动项目(52001013200701)
关键词
斜探头
模态
管道
相速度
频散
angle beam probe
mode
pipe
phase velocity
dispersion
