Research on the frequency stability of a bonded QCM for dew point measurement

A bonded structure of quartz crystal microbalance (QCM) based on finite element method to measure dew point is proposed. Adhesive joints of QCM have dominating impacts on QCM’s stability in a constant environment which is one of crucial problems in designing dew point sensors. Our main purpose is to seek an optimum bonding plan for keeping the frequency stability of dew point sensor. Considering that the QCM mass sensitivity distribution along the surface of the bonded QCM follows a Gaussian-type function, we use R-square as a standard to compare the frequency stability of the structure by changing material and dimension parameters of adhesive joints with the help of APDL language in ANSYS 15.0. At last, four QCMs bonding with various lengths of adhesive joints (L) are chosen for testing time and temperature drift, and the QCM with L less than 2 mm had better frequency stability revealed by partly simulation results.