The flow meter with vortex flow technology shows smaller values when the measured quantity exceeds the range
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A vortex flow meter was installed on a DN25 pipeline to measure saturated steam at 0.4–0.6 MPA. When the valve was opened to about 3/4 of its capacity, the flow meter indicated a maximum flow rate of 200 kg/h; however, as the valve was opened further, the flow rate decreased to 80 kg/h. Is this behavior normal?
I’ve never encountered this situation; it seems that when everything is set to full capacity, the pressure isn’t sufficient to achieve the desired flow rate: lol
This situation is quite complex; it’s possible that the steam contains water, and operating at a low throttle opening increases the dryness, which is why the flow rate is high at such an opening. It is also possible that the distance between the shut-off valve and the vortex flow meter is too short, and the turbulence caused by a partially open shut-off valve affects the flow meter. Or the bluff body inside the flowmeter pipe is eroded, resulting in inaccurate measurement.
The most likely explanation is that at first the steam contains water; after a while, it no longer contains water, and as a result the flow rate decreases, meaning the density changes back from that of water to that of steam.
After ventilation and operation for some time, the situation remained the same. Since the pipeline also comes from the cylinder, is it still more likely that steam contains water?
After the valve was opened wide, the flow rate reading dropped quickly.
Waiting for an expert to provide an answer; staying tuned…
This is possible; vortex flow meters measure volumetric flow rate, and when the valve is opened, the density changes, which may result in a decrease in flow rate