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Venturimeter vs Orificemeter, loss of energy, cost and uncalibrated accuracy.


So what are the differences between Venturimeter and Orificemeter, in terms of loss of energy, cost and their uncalibrated/ un-calibrated accuracies. Let's find out.

Instrument Loss of EnergyInitial CostAccuracy variation with calibration (uncalibrated accuracy)
VenturiVenturi Meter minimizes the form friction and therefore less energy
loss. About 90% is recovered.
Initial cost is higher.They are more accurate than the orifice meter, because they are generally less affected by temperature and corrosion etc. Their discharge coefficient varies with Reynold's number and
variations may be 0.5- 1.5%
OrificeDue to the form friction, a large amount of energy is lost and
unrecovered. Only 60-70% is recovered.
They are in-expensive, because it is just a thin plate with orifice.There are many factors including the sharpness of edges, corrosion, temperature pressure etc. which affect the performance of orifice. If all combined the inaccuracy may range up to 10%. So they are less accurate when uncalibrated.
Thanks for reading.

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