Liao Zuoyu, Zhang Xin, Liu Tianyang, Jia Jiuhong, Tu Shan-Tung
Key Laboratory of Pressure Systems and Safety, Ministry of Education, East China University of Science and Technology, Shanghai 200237, China.
Key Laboratory of Pressure Systems and Safety, Ministry of Education, East China University of Science and Technology, Shanghai 200237, China.
Ultrasonics. 2020 Dec;108:106236. doi: 10.1016/j.ultras.2020.106236. Epub 2020 Aug 11.
Dry-coupled ultrasonic waveguide transducers enable the long-term monitoring of the critical mechanical components working in high temperature environment. In these systems, waveguide units are applied to isolate the vulnerable piezoelectric elements from the harsh measurement zones. However, the disturbance cannot be overcome, which may arise from inevitably temperature fluctuation and the indirect measurement in long term monitoring. In the present research, a high temperature experimental system using dry-coupled ultrasonic waveguide transducers is investigated. The disturbances caused by this measurement system are studied in the heating period, holding period and cooling period, respectively. Moreover, the correlations between the group velocities, dispersion curves, signal amplitudes, waveforms under temperature variations are investigated. At last, the dispersion characteristics of the shear horizontal wave in high temperature stainless steel plate are analyzed. This work strives to pave a solid foundation for the application of SH waves to online monitoring of high-temperature equipment using dry-coupled ultrasonic waveguide transducers.
干耦合超声导波换能器能够对在高温环境下工作的关键机械部件进行长期监测。在这些系统中，导波单元用于将易损的压电元件与恶劣的测量区域隔离开来。然而，在长期监测中，不可避免的温度波动和间接测量可能会产生干扰，而这种干扰无法克服。在本研究中，对一种使用干耦合超声导波换能器的高温实验系统进行了研究。分别研究了该测量系统在加热期、保温期和冷却期所引起的干扰。此外，还研究了温度变化下群速度、频散曲线、信号幅度、波形之间的相关性。最后，分析了高温不锈钢板中水平剪切波的频散特性。这项工作致力于为利用干耦合超声导波换能器将水平剪切波应用于高温设备在线监测奠定坚实基础。
