Institute of Sensor and Actuator Technology, Coburg University of Applied Sciences and Arts, Am Hofbrauhaus 1b, 96450 Coburg, Germany.
Institute of Sensor and Actuator Technology, Coburg University of Applied Sciences and Arts, Am Hofbrauhaus 1b, 96450 Coburg, Germany.
Ultrasonics. 2019 Nov;99:105955. doi: 10.1016/j.ultras.2019.105955. Epub 2019 Jul 15.
Guided acoustic waves, such as Lamb waves, are widely applied for material characterization, sensing of liquids and the generation of streaming in liquids. There are numerical simulation tools for the prediction of their propagation near a solid-liquid boundary but a demand for complementary measurement techniques for the validation of the simulation results remains. In this contribution it is demonstrated that light refractive vibrometry is a suitable approach for the visualization of the interaction of guided acoustic waves with liquids. For this purpose Lamb waves were excited by piezoelectric transducers on copper plates partially immersed in water. There the fundamental symmetric and antisymmetric modes are converted to compressional waves and quasi-Scholte plate waves below a frequency-thickness product of 1 MHz mm. From the vibrometry scans the wavelengths, radiation angles and pressure amplitudes of the involved modes could be determined and thus theoretical predictions of the attenuation of the Lamb modes and the energy distribution of quasi-Scholte plate waves between the solid substrate and the liquid environment could be confirmed.
导声波，如兰姆波，被广泛应用于材料特性分析、液体传感和液体流动的产生。有一些数值模拟工具可用于预测它们在固液边界附近的传播，但仍需要补充测量技术来验证模拟结果。在本研究中，证明了光折射测振法是一种用于可视化导声波与液体相互作用的合适方法。为此，在部分浸入水中的铜板上，通过压电换能器激发兰姆波。在这种情况下，基本对称和反对称模式在频率-厚度乘积低于 1 MHz mm 时转换为压缩波和准 Scholte 板波。通过测振扫描，可以确定所涉及模式的波长、辐射角和压力幅值，从而可以验证兰姆波衰减的理论预测以及准 Scholte 板波在固体基底和液体环境之间的能量分布。
