中国物理B ›› 2016, Vol. 25 ›› Issue (12): 124301-124301.doi: 10.1088/1674-1056/25/12/124301
• SPECIAL TOPIC—Acoustics • 上一篇 下一篇
Selective generation of ultrasonic Lamb waves by electromagnetic acoustic transducers
Ming-Liang Li(李明亮), Ming-Xi Deng(邓明晰), Guang-Jian Gao(高广健)
- Department of Physics, Logistics Engineering University, Chongqing 401331, China
Selective generation of ultrasonic Lamb waves by electromagnetic acoustic transducers
Ming-Liang Li(李明亮), Ming-Xi Deng(邓明晰), Guang-Jian Gao(高广健)
- Department of Physics, Logistics Engineering University, Chongqing 401331, China
摘要：
In this paper, we describe a modal expansion approach for the analysis of the selective generation of ultrasonic Lamb waves by electromagnetic acoustic transducers (EMATs). With the modal expansion approach for waveguide excitation, an analytical expression of the Lamb wave's mode expansion coefficient is deduced, which is related to the driving frequency and the geometrical parameters of the EMAT's meander coil, and lays a theoretical foundation for exactly analyzing the selective generation of Lamb waves with EMATs. The influences of the driving frequency on the mode expansion coefficient of ultrasonic Lamb waves are analyzed when the EMAT's geometrical parameters are given. The numerical simulations and experimental examinations show that the ultrasonic Lamb wave modes can be effectively regulated (strengthened or restrained) by choosing an appropriate driving frequency of EMAT, with the geometrical parameters given. This result provides a theoretical and experimental basis for selectively generating a single and pure Lamb wave mode with EMATs.
中图分类号: (General linear acoustics)
- 43.20.-f