Temperature dependent performance of piezoelectric MEMS resonators for viscosity and density determination of liquids. (15th September 2015)

• Record Type: Journal Article
• Authors: Pfusterschmied, G; Kucera, M; Wistrela, E; Manzaneque, T; Ruiz-Díez, V; Sánchez-Rojas, J L; Bittner, A; Schmid, U
• Is Part Of: Journal of micromechanics and microengineering. Volume 25:Number 10(2015:Oct.)
• Publication Date: 2015-09-15
• Subjects: piezoelectric -- liquid sensing -- MEMS resonators -- elevated temperature; Microelectromechanical systems -- Periodicals; Micromechanics -- Periodicals; 621.38105
• DOI: 10.1088/0960-1317/25/10/105014
• Languages: English
• ISSNs: 0960-1317

Abstract

Abstract: It is the objective of this paper to report on the performance of piezoelectric MEMS resonators for viscosity and density measurements at elevated temperatures. A custom-built temperature controlled measurement setup is designed for fluid temperatures up to 100 °C. Piezoelectric single-side clamped resonators are fabricated, excited in 2nd order of the roof tile-shaped mode (13-mode) and exposed to several liquids (i.e. D5, N10, N35, PAO8, olive oil, ester oil and N100). At the next step, these results are analysed applying a straightforward evaluation model, thus demonstrating that with piezoelectric MEMS resonators the density (i.e. from kg m −3 to kg m −3 ) and viscosity (i.e. from mPa s to mPa s) values of liquids can be precisely determined in a wide range. Compared to standard measurement techniques, the results show for the first parameter a mean deviation of about 1.04% at 100 °C for all the liquids investigated. For the second parameter, the standard evaluation model implies a systematic deviation in viscosity with respect to the calibration being N35 in this study. This inherent lack of strength has a significant influence on the accuracy, especially at 100 °C due to fluids having a viscosity reduced by a factor of 30 for N100 compared to room temperature. This leads to relative deviations of about 23% at 100 °C and indicates the limits of the evaluation model.