摘要
基于频率波数域过滤的波场分离方法场常被用来从波场数据中提取反射波的波场,但由于检测误差的存在,该方法获得的反射波波场中噪声较多。利用高分辨率的激光超声检测,实现了铝板中超声导波波场的可视化,并将波场中相邻信号时间匹配后做差以弱化入射波,而后使用频率波数域过滤的方法对入射波进行深度过滤,对反射波波场进行有效提取。实验结果表明,利用该手段进行二次过滤提取的反射波波场轮廓清晰,所含噪声少。
The method based on frequency-wavenumber domain filtering has great potential in suppressing the incident wave. However, the inspection error can＇t be avoided, the noise in reflection wave fileld got by this method is so much. High-resolution laser ultrasonic testing is used to realize the wavefield visualization in the aluminum plate. Adjacent waves subtraction after arrival time matching and the frequencyiwavenumber domain filtering are both used in this paper to weaken the incident wave. The results show that the proposed filtering method has a good performance in improving the visibility of the damage-reflected wave, and the included noise is less.
出处
《中国激光》
EI
CAS
CSCD
北大核心
2014年第3期149-156,共8页
Chinese Journal of Lasers
基金
国家863计划(2013AA041105)
国家重点实验室自主课题团队项目
2011年度高等学校博士学科点专项科研基金(20113218110026)
江苏高校优势学科建设工程资助项目
关键词
激光技术
超声
波场可视化
频率波数域
无损检测
laser technique
ultrasonic
wavefield visualization
frequency-wavenumber domain
nondestructiveexamination
