All fiber-optic viscosity, density, and temperature measurements of liquids using a photothermally actuated cantilever
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An all-fiber-optical method is presented to monitor densities, viscosities, and temperatures of Newtonian liquids. The actuation is performed by photothermally heating the base of a steel cantilever with an intensity-modulated 808 nm diode laser. The cantilever vibrations are measured with an in-fiber Fabry–Pérot cavity sensor attached along the length of the cantilever. When immersed in a viscous fluid, the cantilever response can be related to the fluid properties: a shift in the resonance frequency corresponds to a change in fluid density, and the width of the resonance peak gives information on the dynamic viscosity after calibration of the system. Aqueous glycerol and sucrose samples in the density range of 0.997–1.17 g cm−3 and in the viscosity range of 0.89–8.49 mPa s were used to investigate the limits of the sensor. Representative beverage samples were also analyzed as unknowns.
The authors gratefully acknowledge financial support by the Natural Sciences and Engineering Research Council (NSERC) of Canada.
- 19.J.H. Lee, J.H. Yoo, S.Y. Yim, S.H. Park, Symmetric and asymmetric resonance characteristics of a tuning fork for shear-force detection. J. Korean Phys. Soc. 45(2), 455–459 (2004)Google Scholar
- 20.J. Gere, Mechanics of Materials, 6th edn. (Thomson-Engineering, Brooks, 2003)Google Scholar
- 25.A.I. Freytag, Fiber-Optic Vibration Sensing of Cantilevers Immersed in Fluids (Masters of Science, Chemistry, Queen’s University, Kingston, 2016)Google Scholar
- 26.J.F. Swindells, C.F. Snyder, R.C. Hardy, P.E. Golden, Viscosities of sucrose solutions at various temperatures: tables of recalculated values, in Supplement to National Bureau of Standards Circular 440 (1958). https://hdl.handle.net/2027/mdp.39015077295460. Accessed 9 Oct 2018
- 29.C. Westbrook. Calculation of density and viscosity of glycerol/water mixtures. (2018). http://www.met.reading.ac.uk/~sws04cdw/viscosity_calc.html. Accessed 9 Oct 2018