10 Technical data Proline Prowirl 72 FOUNDATION Fieldbus
62 Endress + Hauser
10 Technical data
10. 1 Technical data at a glance
10.1.1 Application
The measuring system is used to measure the volume flow of saturated steam, superheated steam,
gases and liquids. If the process pressure and process temperature are constant, the measuring
device can also output the flow as the calculated mass flow and corrected volume flow.
10.1.2 Function and system design
Measuring principle Vortex flow measurement on the principle of the Karman vortex street.
Measuring system The measuring system consists of a transmitter and a sensor:
• Prowirl 72 FOUNDATION Fieldbus transmitter
• Prowirl F or W sensor
Two versions are available:
• Compact version: Transmitter and sensor form a single mechanical unit.
• Remote version: Sensor is mounted separate from the transmitter.
10.1.3 Input
Measured variable Volumetric flow (volume flow) is proportional to the frequency of vortex shedding after the bluff
body.
Volume flow can be output as the output variable, as can the calculated mass flow or corrected
volume flow if process conditions are constant.
Measuring range The measuring range depends on the fluid and the pipe diameter.
Start of measuring range
Depends on the density and the Reynolds number (Re
min
= 4000, Re
linear
= 20 000). The Reynolds
number is dimensionless and indicates the ratio of a fluid's inertial forces to its viscous forces. It is
used to characterize the flow. The Reynolds number is calculated as follows:
A0003794
Re = Reynolds number
Q = Flow
di = Internal diameter
= Dynamic viscosity
=
Density
A0003239
Re
=
4·Q · m³[m³/s] [kg/ ]
di [m] · µ · [Pa·s]
Re
=
4·Q · ³[ft³/s] [lb/ft ]
di [ft] · µ · [0.001 cP]
Re
=
4·Q · m³[m³/s] [kg/ ]
di [m] · µ · [Pa·s]
v
½…1"
=
min.
4.92
[lb/ft³]
v
1½…12"
=
min.
5.74
[lb/ft³]
[ft/s] [ft/s]
v
DN 15…25
=
min.
6
[kg/m³]
v
DN 40…300
=
min.
7
[kg/m³]
[m/s] [m/s]
*
*
*
*
To Next Page
Loading...
