摘要 |
A Coriolis-type fluid flow rate measuring system splits a fluid flow that is to be measured into two equal half flows and passes the same respectively through two physically similar conduits which are oscillated about respective parallel oscillation axes. Analog sinusoidal signals corresponding to relative velocity of motion between the two conduits are obtained at two locations, the analog signals a digitized, and a conventional microprocessor is used to apply a least-squares sine fit to the digitized data to determine to a very high degree of accuracy a phase shift between the signals. An empirical proportionality factor is determined for the system to relate phase shift to fluid flow rate and is used to determine the fluid flow rate. The least-squares sine fit provides an accurate, economically computed fluid flow rate, and the apparatus is highly insensitive to temperature induced effects, harmonic distortions, and the combined effects of noise and harmonic distortion.
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