Thermal frequency drift of Diaphragm Resonant Sensors
Virginia Polytechnic and State Univeristy, US
Keywords: Sensors, thermal, frequency drift, circular diaphragm
Resonant senosrs and microsensors are one of the most common used sensors in industry. The applications ranges from fuid, pressure to chemical sensing.
Temperature effect on the performance of such devices is of importance to the accuracy of measurement
Some work was carried out with respect to beam sensors to study this phenomenon, but nothing with respect to diaphragm sensors to the author knowldge.
In this paper, we are interested in the modeling of such diaphragm under thermal effect. We chose the dynamic analogue of Saint-Venant plate model under uniform temperature to analyse a circular diaphragm.
The resulting equation turns out to be similar to the classic problem of plate stability under uniform in-plane loading. The modeling methodology can be applied to any type of thermal loading and the complications would be only the possibility of solving the resulting stability problem.
It is found that under the assumption of isotropic materials with temperature-insensitive material properties, the frequency drift depends mainly on the temperature and the material properties are of no significan influence. Also, we show that the frequency-temperature relationship is nonlinear for the first mode but almost linear for higher modes. To this end, the designers should be able to control properly the temperature effects on such sensors.
NSTI Nanotech 2003 Conference Technical Program Abstract