Patent ID: 11913816
Assignee: ENDRESS+HAUSER FLOWTEC AG
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 12:
13. A measuring point for determining a flow profile independent flow velocity or volume flow rate of a medium, the measuring point comprising:
a magnetic-inductive flow meter for measuring flow velocity or volume flow rate of the medium, the flow meter comprising:
a measuring tube configured to convey the medium in a longitudinal direction defined by a measuring tube axis, wherein the measuring tube has an inlet side end plane and an outlet side end plane, which bound the measuring tube in the longitudinal direction, wherein the measuring tube includes a passageway, which includes a wall bounded by a liner;
at least one magnetic field generator configured to generate a magnetic field in the medium extending essentially perpendicular to the longitudinal direction, wherein the magnetic field generator includes a pole shoe or a saddle coil, and wherein the pole shoe or the saddle coil in a cross-sectional area of the measuring tube subtends the measuring tube or the passageway with a maximum central angle; and

an electrode system including at least two electrode pairs, each configured to detect a voltage induced in the medium perpendicular to the magnetic field and to the longitudinal direction, wherein:
a vertical measuring tube longitudinal plane divides the measuring tube into a first side and a second side;
in each case, a first electrode of an electrode pair of the at least two electrode pairs is disposed on the first side of the measuring tube;
in each case, a second electrode of the electrode pair is disposed on the second side; and
a central angle in the cross-sectional area of the measuring tube defines a minimum circular sector in which each electrode disposed on either the first or second side of the measuring tube are distributed,

wherein the central angle and the maximum central angle are configured relative to each other such that the flow meter is insensitive to departures from a rotationally symmetric flow of the medium because of a disturbance source applied with a separation of 0-DN at the inlet side end plane, and
wherein the flow meter has a measurement error of flow velocity defined by, Δ
   u
  
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    ❘
    "\[LeftBracketingBar]"
   
   
    
     
      u
      
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    ❘
    "\[RightBracketingBar]", and/or a measurement error of volume flow rate defined by, Δ
   
    V
    .
   
  
  =
  
   
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    ❘
    "\[RightBracketingBar]", less than 1.0%, wherein:

uva and uS are flow velocities, and {dot over (V)}va and {dot over (V)}S are volume flow rates of the medium;
the flow velocity uva and the volume flow rate {dot over (V)}va are determined in the case of a flow of the medium with fully developed flow profile; and
the flow velocity uS and/or the volume flow rate {dot over (V)}S are determined in the case of the applied disturbance source.