دانلود رایگان مقاله انتشار موج هدایت شده در ورق فولاد غوطه ور آب یک طرفه

Abstract

This paper presents a case study of guided waves in a steel plate with one side immersed in water. A hybrid sensing system that uses PZT as the guided wave actuator and a scanning laser vibrometer as the guided wave receiver is employed to acquire the time–space wavefield data. By using the two dimensional Fourier transform, the time–space wavefield is transformed into the frequency–wavenumber domain where the wave modes and the guided wave dispersion can be determined. The study confirms the existence of quasi-Scholte wave in the one-sidedly water-immersed plate in addition to fundamental guided waves. The results also show the quasi-Scholte wave can be directly generated and measured in the immersed plate at low frequencies using the present sensing system. Through pitch–catch sensing tests, the influence of water on guided wave propagation in the one-side water-immersed plate is investigated. It is seen that the water level affects the wave propagation time linearly and can be potentially used for estimation of water level in a container.

4. Conclusions

In this paper, we presented a case study of guided wave propagation in a plate with one side immersed in water. With the acquisition of time–space wavefield and application of 2D FT, the frequency–wavenumber spectrum is obtained in which the wave modes and the dispersion relation can be discernibly viewed. The analysis also manifests the presence of guided wave modes as well as the quasi-Scholte wave mode in the one-sidedly immersed plate. Below 300 kHz, the quasi-Scholte mode dominates. The investigation of water influence on the wave propagation shows the wave traveling time in a partially immersed plate is determined by the length of the water path and the dry path. A linear relationship between the change of traveling time of the waves and the water level is experimentally confirmed.