BrianMarxCim
Member
I have a DP Meter that works fine however if I change the temperature of the fluid then there are discrepancies. If I add a rtd to the line how do I calculate the flow based on the temperature?
Is the fluid a gas or a liquid? Are you looking for volumetric or mass flow rate? How do you know there are discrepancies?
I have a DP Meter that works fine however if I change the temperature of the fluid then there are discrepancies. If I add a rtd to the line how do I calculate the flow based on the temperature?
The best reference for flow meter calculations is probably ASME PTC 19.5. https://www.asme.org/products/codes-standards/ptc-195-2004-flow-measurement-(1)
The constants etc. are different for pitot tubes, orifices, venturis, etc. Your flow meter supplier shouldbe able to provide you with the proper formulas and technical data. Like Lare, I am skeptical that the temperature difference is an issue unless you are looking at some very accurate measurements.
Here is a formula, though: http://www.engineeringtoolbox.com/fluid-density-temperature-pressure-d_309.html
Are you using an orifice plate? Venturi?
What type of instrument is mounted to flow device?
Any chance there is air getting caught in the sampling tube? Have you blown down/ cleaned the sampling tubes?
Is this a new installation or one that has been working for years and just now giving you problems?
We are looking for very accurate numbers, Thanks for your help!
We have created our own venturi, We are looking to get as accurate as is possible.
If you have created your own venturi, have you sent it to a recognized flow lab to be tested/calibrated?
http://www.ceesi.com/