What methods are people using in DCS calculations for superheated steam orifice plate flowmeters?
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Hello, everyone! The density of superheated steam is a fitted value. To ensure accuracy, how do high-pressure superheated steam orifice flow meters function in calculating flow rates within a DCS system?
How should I put it? Just add thermal and pressure compensation, right! To reduce pressure loss, balanced porous materials are used; however, there are no national standards for other types
If there is a steam density database such as IF97, the density can be retrieved and used in the calculations. There are also formulas that use normal gas temperature and pressure for compensation, but the error will be larger.
I couldn’t find a module in the PLC for calculating the density of superheated steam; I’ve also used it in domestic DCS systems, and the overall error remains quite large. But recently I found some steam density compensation formulas with decent accuracy.
https://bbs.hcbbs.com/thread-3199995-1-1.html Check out my post and you’ll find the answer.
Yes, I also resolved it using this method.
The diameter isn’t very large, so vortex flow meters can be used directly; Yokogawa’s vortex flow meters offer temperature and pressure compensation, which makes them simple to use. As for orifice plates, it’s difficult to maintain consistent conditions in the positive and negative pressure tubes, and over time problems may arise with the holes in the orifice plate.