Energy leakage and attenuation analysis of APM with liquid loading

Acoustic Plate Mode Wave (APM) device is suitable for liquid-phase measurement. The appearance of liquid loading would lead to the energy leakage of APM and the reasons are various. According to acoustic wave propagation theory in the layered medium, this paper establishes the APM analysis model with liquid loading. Using non-viscous liquid, conductive liquid and viscous liquid as examples, by numerical simulations of general APM, sagittal APM and shear-horizontal APM, the APM energy leakage with liquid loading is researched, and the reasons are concluded. Furthermore, the two-dimensional analysis model of leaky APM is established by adding attenuation factor in the expressions of acoustic field components. The leaky APM propagation velocity and attenuation factor are obtained by the method of “surface effective permittivity rough-searching” added by “boundary conditions coefficient determinant refined-searching. The APM devices are designed and tested. The experimental results are in agreement with the numerical simulations.