Sensor Installation Handbook Preface 3rd edition - Siemens ...

Measuring water velocity and flow
Like air velocity, water velocity can be measured with orifice plates.
Velocity measurements, however, are primarily required in order to determine
heat volume.
There are various commercially available heat meters, based on different
mechanisms for measuring flow velocity.
Example:
Orifice Impeller Ultrasound Magnetic flux
Inductiv
Important:
The required steadying zones must be allowed for, upstream and
downstream of the sensor.
Flow velocity
To determine the flow velocity, the differential
pressure at the flow detector (orifice plate,
flow grid etc.) is measured. The same general
mounting instructions apply as for differential
pressure sensors.
Important:
The required steadying zones must be allowed
for, upstream and downstream of the sensor.
Formula:
dg = Equivalent diameter
Velocity
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