A MEMS Vibrating Edge Supported Plate for the Simultaneous Measurement of Density and Viscosity: Results for Argon, Nitrogen, and Methane at Temperatures from (297 to 373) K and Pressures between (1 and 62) MPa

An edge supported plate fabricated by the methods of MicroElectroMechanical Systems (MEMS) is described that differs from the device reported by Goodwin et al. (J. Chem. Eng. Data 2006, 51, 190−208) in both design and plate area, which is about 2.4 times greater in this case. Two decoupled semiempirical equations are used, one for density and the other for viscosity, as reported by Goodwin et al. (J. Chem. Eng. Data 2006, 51, 190−208). Measurements were performed when a MEMS was immersed in argon, nitrogen, and methane at T ≈ 296 K and pressures between (1 and 8) MPa and when another similar MEMS was immersed in argon and nitrogen at temperatures between (333 and 393) K and pressures in the range (20 to 62) MPa where the fluid viscosities are known to vary from (11 to 50) μPa·s and the densities cover the range (11 to 672) kg·m−3. The unknown parameters in the semiempirical working equations were determined by calibration with argon. For the device exposed to pressures between (1 and 8) MPa for argon, nitrogen, and methane, the empirical expressions provided estimates of density within ± 0.5 % and viscosity typically within ± 1 % of the literature values, while the other device used for measurements with argon and nitrogen at pressures between (20 and 62) MPa at temperatures in the range (333 to 393) K gave densities that differed < ± 1 % and viscosities within ± 15 % of literature values.