META SLAB ULTRASONIC TRANSDUCERS FOR FLOW VELOCITY MEASUREMENT WITH META SLAB

摘要

An ultrasonic transducer with a meta slab comprises a piezoelectric body for generating an elastic wave, a meta slab connected to the piezoelectric body and inducing an elastic mode conversion resonance phenomenon with respect to an incident elastic wave, and a wedge connected to the meta slab and attached to an outer surface of a pipe to transmit the elastic wave passing through the meta slab to the pipe. The meta slab is an anisotropic material and a thickness satisfies the following formula such that a flow rate can be measured with high efficiency, wherein the formulas are represented as d=m*n_(FS)*(λ_(FS)/4), d=m*n_(SS)*(λ_(SS)/4), and n_(SS)/2-n_(FS)/2=odd.