US 12,111,192 B2
Magnetic-inductive flow meter and method for operating a magnetic-inductive flow meter
Simon Mariager, Basel (CH)
Assigned to Endress+Hauser Flowtec AG, Reinach (CH)
Appl. No. 17/628,602
Filed by Endress+Hauser Flowtec AG, Reinach (CH)
PCT Filed Jun. 18, 2020, PCT No. PCT/EP2020/066993
§ 371(c)(1), (2) Date Jan. 20, 2022,
PCT Pub. No. WO2021/018470, PCT Pub. Date Feb. 4, 2021.
Claims priority of application No. 102019120315.5 (DE), filed on Jul. 26, 2019.
Prior Publication US 2022/0276081 A1, Sep. 1, 2022
This patent is subject to a terminal disclaimer.
Int. Cl. G01F 1/58 (2006.01); G01F 1/60 (2006.01); G01N 11/00 (2006.01)
CPC G01F 1/588 (2013.01) [G01F 1/60 (2013.01); G01N 11/00 (2013.01); G01N 2011/0026 (2013.01)] 15 Claims
OG exemplary drawing
 
1. A magnetic-inductive flow meter, comprising:
a measuring tube adapted to conduct a flowable medium and including a wall;
at least three measuring electrodes disposed in the wall such that each measuring electrode is in galvanic contact with the flowing medium;
at least one magnetic field-generating device configured to generate a magnetic field that passes through the measuring tube;
a measuring circuit configured to determine at least one measurement variable, wherein measured values of a first measurement variable of the at least one measurement variable are determined at a first measuring electrode pair, which includes two measuring electrodes of the at least three measuring electrodes; and
an analysis circuit configured to determine a Reynolds number and/or a kinematic viscosity value of the medium in the measuring tube using measured values of the first measurement variable and a second measurement variable, which differs from the first measurement variable,
wherein measured values of the second measurement variable are determined at a second measuring electrode pair or at a third measuring electrode relative to a reference potential, and wherein the at least three measuring electrodes are arranged in the measuring tube such that, in a test measurement, quotients of current measured values of the first and second measurement variables correspond bijectively to the Reynolds number (Re) of the flowing medium in the measuring tube, at least within a Reynolds-number range of 1,000≤Re≤1,000,000.