The influence of viscous and conducting liquid on the characteristics of the slot acoustic wave

• Published in: Ultrasonics Vol. 82; pp. 39 - 43
• Main Authors: Borodina, I.A., Zaitsev, B.D., Teplykh, A.A.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01-01-2018
• Subjects: Conductivity; Permittivity of liquid; Piezoelectric plate; Resonant peaks on the frequency dependency of insertion loss; Shear – horizontal acoustic wave of zero order; Slot mode; Viscosity; Viscosity; Shear – horizontal acoustic wave of zero order; Conductivity; Permittivity of liquid; Slot mode; Piezoelectric plate; Resonant peaks on the frequency dependency of insertion loss
• ISSN: 0041-624X; 1874-9968
• DOI: 10.1016/j.ultras.2017.07.011

•Device including plate delay line and piezoplate separated by air gap is presented.•Slot wave in such device leads to resonant peaks on frequency dependence of loss.•Changes of viscosity of liquid contacting with piezoplate vary only depth of peaks.•Changes of parameters of conducting liquid vary frequency and depth of peaks.•Such device may be used for identification of conducting and viscous liquids.
The influence of the liquid with the different values of conductivity, permittivity, and viscosity on the characteristics of the slot mode in the structure consisting of delay line with propagating shear – horizontal acoustic wave of zero order (SH0) and upper piezoelectric plate separated by the air gap was experimentally investigated. The delay line made of the Y-X lithium niobate plate 0.2mm thick contained two interdigital transducers for the excitation and reception of acoustic wave in the frequency range of 2.6–3.8MHz. The upper plate represented the 0.5mm thick plate of Z-X lithium niobate. The excitation of the slot mode led to the appearance of the sharp resonant peaks on the frequency dependencies of insertion loss and phase of the output signal. It has been found that the depth and frequency of these peaks depend on the parameters of liquid contacting with the upper plate. The possibility of the use of the slot mode in the pointed structure for the identification of liquids with the different values of the conductivity, viscosity, and permittivity was shown. The qualitative explanations of the obtained experimental results are presented.