Waterworks
IOM
Sensors
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The greater the diameter of the pipe, the higher the speed of the liquid will be required to move the air pockets
away from the flowmeter.
It is also important to understand what kind of effect the water pressure has on the nature of the air pocket
inside the pipe. The lower the pressure in the tube, the greater the size of the air pocket is, and the greater the
effect it will have on the performance of the flowmeter. By increasing the pressure in the duct, the air pocket
will compress, causing fewer problems.
This can be achieved by installing pressure control valves after the flowmeter to maintain constant pressure in
any situation.
One solution is to install the flowmeter on a pipe with an increasing slope so that the entrapped air pocket will
move to the highest point. Then, through special vent valves, the air will be released from the pipe, maximizing
the system capacity.
Fig. 37 Air pockets inside the pipe
Fig. 38 Example of pressure control valves
Fig. 39 Pipe with an increasing slope for application of vent valves
