摘要 |
<p>Disclosed is an apparatus for estimating a property of a fluid. The apparatus includes: a piezoelectric resonator configured to be disposed in the fluid; an electrode embedded in the piezoelectric resonator and included in a resonator circuit configured to output an electrical signal related to the property; a discontinuity defined by a surface of the piezoelectric resonator, the discontinuity altering an impedance of the resonator circuit if a high-dielectric fluid or a conductive fluid is disposed in the discontinuity; and an insulating material disposed in the discontinuity.</p> |