2 replies to this topic

[Ranga v]

Dear Gents,

 

For the nitrogen flow measure ment we have DP type transmitter having range 0-2500 MMWC ,variance ,diff between custody meter which is ultrasonic  is observed at a lower flows < 1000 Nm3/hr . With current DP what are the options for reducing the difference  

[breizh]

hi,

Google search AI mode.

 

"Rangeability (or turndown ratio) is the ratio of maximum measurable flow to minimum measurable flow while maintaining specified accuracy. Mass flow meters (e.g., Coriolis) significantly outperform Differential Pressure (DP) flow meters in rangeability. [1, 2, 3, 4, 5]

A clear comparison of their capabilities is outlined below: [1]

 

Differential Pressure (DP) Flow Meters

• Typical Rangeability: \(3:1\) to \(10:1\) [1]
• Why it's lower: DP meters (like orifice plates) use a square-root relationship between the measured pressure drop and the flow rate, represented by \(Q \propto \sqrt{\Delta P}\). Because of this, accuracy degrades significantly at low flow rates. [1, 2, 3, 4, 5]
• Improvement: Modern transmitters can push rangeability to about \(10:1\) or \(14:1\), and specialized "stacked" transmitters (using two sensors on one element) can reach \(20:1\) or higher by measuring different spans. [1, 2, 3]"

You may have to change the technology and chose Coriolis meter.

Should be crystal clear from above.

 

Breizh

[Ranga v]

Thanks