摘要
为了实现对冷凝器不锈钢波纹管的主动健康监测,采用附着在结构上的压电陶瓷晶片以及套在结构表面的电磁声换能器激励接收导波模态,优化各种参数以用于缺陷的识别和评估。试验选取经Hanning窗调制的正弦脉冲信号在波纹管中激励中心频率240kHz的纵向超声导波L(0,2)模态,用于波纹管中人工缺陷的检测,并分析了L(0,2)模态对不同类型缺陷的敏感程度。试验结果表明,利用压电陶瓷晶片和电磁声传感器激励接收频率为240kHz的L(0,2)模态可以识别波纹管中的裂纹缺陷。
The guided wave modal was incentive received and parameter was optimized for the identification and evaluatio.n of defects by the piezoelectric ceramic crystal chips attached to the structural and the electromagnetic acoustic energy transducer set in the structure surface in order to realize the active health monitoring for stainless steel bellows of condenser. Longitudinal ultrasonic guided wave L （0,2） mode of 240kHz incentive center frequency in bellows of sine pulse signal modulated by Hanning window was selected for the detection of bellows＇ artificial defect. And the sensitive degree of analyzes L （ 0,2 ） modal for different types＇ defects was analyzed. The experimental results showed that, using the piezoelectric ceramic crystal chips and electromagnetic acoustic energy transducer to incentive receive the L（0,2） modal of 240kHz frequency could identify the crack defects of bellows.
出处
《汽轮机技术》
北大核心
2012年第2期112-114,共3页
Turbine Technology
关键词
超声导波
波纹管
模态
电磁声换能器
裂纹
ultrasonic guided wave
bellow
model
electromagnetic acoustic energy transducer
crack
