Symmetric Plate Resonators for Viscosity and Density Measurement

In this contribution, we present a symmetric arrangement of resonating plates for viscosity and mass density measurement. Regarding the oscillation mode, the design resembles that of micro machined tuning forks and is based on previously introduced resonating plate designs. It exhibits similar sensitivity to viscosity and mass density as the single plate resonators while having a lower damping when operated in the tuning fork mode. In this contribution we introduce the new design, present the results of FE simulations in order to determine the associated eigenmodes and examine the effects of the used actuation method on the sensor. Measurement results are presented which show the general dependence of the tuning fork design on viscosity and mass density as well as the differences exhibited by different modes, particularly the in phase and out of phase vibration modes of the plates.