Fluid property and flow sensing via a common frequency generator and FFT
Patent 6169965 Issued on January 2, 2001. Estimated Expiration Date: December 31, 2017. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
702/136, Thermal related property73/61.76, By thermal measurement374/43, DETERMINATION OF INHERENT THERMAL PROPERTY (E.G., HEAT FLOW COEFFICIENT)374/137, Temperature distribution or profile702/50Fluid measurement (e.g., mass, pressure, viscosity)
A method and apparatus for using a common frequency generator for measuring selected properties of a fluid of interest via one or more heater and/or sensor elements. The common frequency generator may sequentially and/or simultaneously provide input signals to selected heater and/or sensor elements. Application of more than one frequency component by the common frequency generator enables the determination of one or more time and/or phase lags more efficiently, especially when using an FFT analysis technique. From the time and/or phase lags, the selected fluid properties including fluid flow speed can be determined.
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December 31, 2017. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
