Density correction for orifice plate flowmeters
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For orifice plate flowmeters used to measure methanol, when there is a discrepancy between the actual density and the designed density, how can this be compensated for?
Online temperature and pressure compensation – right there. . . .
Compensatory adjustments are not possible; the differential pressure value obtained from orifice plate measurements must be calculated using the original process parameters, and a calculation report must be prepared. If it’s a gas, temperature and pressure compensation can be used, as the density of a gas is proportional to temperature and pressure. But methanol is a liquid, so this approach doesn’t work; it’s necessary to prepare new calculations and adjust the range of the differential pressure transmitter.
Is there any software? Once the hole diameter is fixed, re-enter the temperature, density, and viscosity values, and then calculate the differential pressure. Try Flowcal, this software
Does that mean changing the range of the differential pressure value? Are there any other methods, such as the corresponding range?
Well, isn’t that just the corresponding range you’re talking about? The main thing is to redo the calculations or formulas in order to determine the value of K under the current conditions, before moving on to the next step. The flow rate is proportional to the square root of the differential pressure, and this coefficient is the K value. Whether changing the flow rate range or the differential pressure range, it is necessary to first determine the value of this K value.
Was methanol originally a liquid? Damn it, Tana Naided; I’m completely clueless when it comes to chemistry. . Only now did I understand: what the original poster means by “compensation” here is asking how to correct the flow coefficient. For liquids, it’s extremely simple – as simple as the curve of a bubble. The formula is as follows: Actual flow coefficient = Design flow coefficient × square root of (Design density ÷ Actual density). . In case brother is wrong, it’s your bad luck then – after all, I’m an idiot when it comes to chemistry. . .