1. Pipe lines and process parameters:
ID*WD: 83 * 5mm
medium: air
Design temperature /pressure: 24℃ / 79.4kPaA
Operation density: 1.293 kg/m3
Scale/max/nor/min flow: 178 / 110 / 38 /16 Nm3/h
Primary element: T26
K coefficient: automatic calculation
Expansion coefficient: 0.99983
Experimental Procedures and Introduction:
(1) A 83mm pipe with 3 flow instruments for measurement the same flow,
①One Mikoflow MV 4-into-ONE flow meter with one T26 (Probe bar) as primary element (A);
②Changing 83mm pipe into 50mm diameter, which mounted another Mikoflow T12 (another kind of probe bar) connects 4-into ONE flow meter (B)
③One 0.5%R vortex flowmeter (C), mounted on ID=83mm pine.
(2) The air volume of the pipeline is controlled by the variable frequency fan; the frequency converter runs from (4.6~50) Hz.
① At 4.6Hz, the A / B table starts to output, about 2.4Pa, 16 N m3/h, velocity is only 1m/s
② The output for vortex (C) does not start until about 10Hz (38 N m3/h), three flow meters’ output will be closed, DP is about 11Pa, velocity is about 2.6m/s, which is the min flow for vortec flowmeter.
③ The frequency converter is 4.6/5/7/10/20//30/50/5/4.6Hz respectively, which can see the curve of two Mikoflow MV flowmeters from the two 4.6 Hz (forward stroke and reverse stroke), but (2.2~2.3) Pa, about 16 Nm 3 / h, so the repeatability of T26/T12 is very good.
(3)Other photos and videos of the new generation membrane box prototype (developed at Aug. 2021), compared with the differential pressure transmitter with ± 0.035% accuracy (Japan).
