Measurement of Liquid Properties with Resonant Cantilevers

Liquid viscosity and density sensors are essential devices in online process or condition monitoring. Microacoustic sensors combine advantages such as small size, low cost, and absence of macroscopically moving parts. However, these devices feature measurement at high shear rates and, therefore, the results may diverge from those obtained with traditional viscometers. In our contribution we investigate a PZT driven bending actuator and a micromachined doubly clamped bridge device for use as viscosity and density sensors. The presented models allow the description of the sensor’s interaction with the surrounding liquid.