Measurement solutions for low-pressure hydrogen and low-flow hydrogen: how to address it
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:'(There is an existing operating condition with hydrogen as the medium, and its purity is high after electrolytic drying. Pressure: 0.2 MPa, temperature: 30°C; typical flow rate range: 90–130–150 standard cubic meters. The control requirement is an error of less than 1 standard cubic meter (anything more than that is not acceptable; a value within 1.5 standard cubic meters is acceptable). This is annoying! We have been using domestic mass flow meters until now, and the control performance is far from meeting the requirements. Experts, what is the best solution? Thank you!
I am currently in contact with manufacturers of orifice plates, imported mass flow meters, and thermal mass flow meters; all of them say that it is possible to carry out measurements, but I’m not sure yet – I don’t know if it will actually work!
Bro, add me on WeChat and I’ll help you with the selection process. My contact number is 15060667089. You didn’t mention how thick your pipes are; I can guarantee that there will be no issues, though it’s a relative error. In other words, if the actual flow rate is 5 cubic meters, and under normal operating conditions, the measurement result won’t exceed 4.95 to 5.05 cubic meters. This can be included in the contract
The **standards for vortex flowmeters are established by our company. After conducting calculations, we find that under these pressure and temperature conditions, our company can measure flow rates ranging from 40 to 481 standard cubic feet with an error of less than 1%. My WeChat ID is 15060667089; we have many successful practical cases related to hydrogen
Hydrogen has a very low density, so it is difficult to achieve high precision when measuring it by mass. The principle of a Coriolis mass flow meter is that when fluid flows through a vibrating tube, a Coriolis force proportional to the mass of the fluid is generated, and an electrical signal is produced as a result of this force acting as a torque. Hydrogen has such a low density, so the torque it generates is also very small. Of course, it’s very difficult to use well
For pipe 25, I just don’t know how it’s used!
The thermal type is also on our consideration list; we looked at the FCI thermal mass models, and the results from the calculations seem satisfactory, though the price is indeed high. What’s lacking are real-life examples around us that can serve as a reference; having such experiences makes one feel much more confident when using this approach.
Hydrogen has a low density, and with flow meters of the vortex-type, it is difficult for the sensor to generate a signal as a result of being rotated by the hydrogen and then struck. This is hard to solve. We have practical solutions; with low-pressure hydrogen, it is very difficult to detect small flow rates using vortex flow meters. According to relevant information, vortex flowmeters are not recommended when the density is below 0.5 kg/m3; this is a priority consideration in selecting a flowmeter.
A MEMS thermal mass flow meter + actual flow calibration is sufficient to solve it.