Abstract:
A method for ascertaining a Reynolds number compensated flow velocity and/or a Reynolds number compensated flow (G) by a Coriolis flow measuring device, comprising steps as follows: a. ascertaining at least one meter factor (C) during a calibration time interval in a calibration plant (a) based on measured values (A and B) of the Coriolis flow measuring device and a piston test apparatus of the calibration plant (a) by an evaluation unit of the calibration plant (a); b. transmitting the meter factor (C) from the evaluation unit of the calibration plant (a) to an evaluation unit of the Coriolis-flow measuring device; c. associating a Reynolds number (H) with this meter factor (D) while the Coriolis flow measuring device is connected to the calibration plant (a), and storing at least one data set of at least one number pair (D), in each case, of a Reynolds number and a meter factor, in the Coriolis flow measuring device; d. ascertaining an uncorrected measured value (E) for a flow velocity and/or a flow of a measured medium (M) at a measuring point (b), the density of the measured medium (M) at the measuring point (b) and the viscosity of the measured medium at the measuring point (b); e. ascertaining a Reynolds number based on the measured value (E) of the flow velocity and/or flow, the density and the viscosity of the measured medium (M) determined in step d) and associating a meter factor (C) with this Reynolds number; and f. correcting the uncorrected measured value (E) of flow velocity and/or flow based on the associated meter factor (C) and outputting the Reynolds number-corrected flow velocity and/or the Reynolds number-corrected flow (G), and a Coriolis flow measuring device.
Abstract:
A flow measuring device for ascertaining a corrected measured value of a flow velocity and/or a corrected mass flow of a medium, especially a gas, in a measuring tube, including: an apparatus for ascertaining a first measured value of flow velocity and/or mass flow of the medium by thermal, mass flow measurement; an apparatus for ascertaining velocity of sound and/or frequency dependent damping of an acoustic signal, especially an ultrasonic signal, in the medium and/or an apparatus for ascertaining an optical, wavelength dependent absorption of an optical and/or excited fluorescence of the medium, and an evaluation unit for correcting the ascertained first measured value of mass flow or flow velocity based on the ascertained sound velocity values and/or the frequency dependent, ascertained damping values of the acoustic signal and/or the ascertained absorption values of the optical signal and/or the florescence values of the medium, and method for ascertaining a corrected measured value of flow velocity and/or mass flow, and use of the device and method.
Abstract:
A flow measuring device for ascertaining a corrected measured value of a flow velocity and/or a corrected mass flow of a medium, especially a gas, in a measuring tube, including: an apparatus for ascertaining a first measured value of flow velocity and/or mass flow of the medium by thermal, mass flow measurement; an apparatus for ascertaining velocity of sound and/or frequency dependent damping of an acoustic signal, especially an ultrasonic signal, in the medium and/or an apparatus for ascertaining an optical, wavelength dependent absorption of an optical and/or excited fluorescence of the medium, and an evaluation unit for correcting the ascertained first measured value of mass flow or flow velocity based on the ascertained sound velocity values and/or the frequency dependent, ascertained damping values of the acoustic signal and/or the ascertained absorption values of the optical signal and/or the florescence values of the medium, and method for ascertaining a corrected measured value of flow velocity and/or mass flow, and use of the device and method.