Micro Flow Sensor Based on Frequency Measurement of Micro Whistles

Abstract:

In this work, several millimeter sized micro whistles have been tested as potential frequency analog gas flow sensors. The characteristic curves of the whistles were systematically investigated as a function of geometrical dimensions, the kind of gas applied, and temperature. Both a micro¬phone and a PVDF foil were employed to record the frequencies. The relation be¬tween oscillation frequency and volume flow rate only shows a weak function of fluid properties and temperature. At a given flow rate, the difference of argon and nitrogen is 120 Hz on average, which is corresponding to 1.4 %. For air flow at a given flow rate, frequency rises approximately 380 Hz (2.73 %) per 10 °C. This kind of micro whistle could be employed as gas flow sensor which is insensitive to fluid properties.

• Periodical: Advanced Materials Research (Volumes 468-471)
• Pages: 2061-2064
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.468-471.2061
• Online since: February 2012
• Authors: Yan Bin Di, Ying Miao
• Keywords: Flow Sensor, Fluid Properties, Frequency, Micro Whistle, Oscillator, Polymer

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