This calculator performs the flow rate calculation from the measured pressure drop caused by the orifice plate inserted in the pipeline.

The calculator is suitable for liquids and perfect gases, a subsonic flow of single phase fluid.

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Monthly cost

$250/month

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OrificeAirD, d, p_{1}, p_{2}, TQ

Task: Calculate flow rate of air through the orifice plate. Orifice internal diameter is 100mm, and tube where orifice is inserted, internal diameter is 200mm. Pressure in front of the orifice is 104000 Pa, and pressure after the orifice is 100000 Pa absolute. Pressures are measured on the corner taps. Temperature of air is 15 C.

Solution:
Flow rate is: 1374.5 m^{3}/h

OrificeWaterD, d, p_{1}, p_{2}, TQ

Task:
Calculate flow rate of water flowing through orifice plate with external diameter of
120 mm and internal diameter of 80 mm. Measured pressures in front and after the orifice
is 11000 mm H_{2}O and 10000 mm H_{2}O. Pressure is measured on 1 inch taps.

Solution: Flow rate is: 54.674 m3/h

OrificeWaterD, d, p_{1}, p_{2}, TQ

Task: Calculate flow rate of water through the orifice with external diameter of 200 mm, internal diameter of 160 mm. Measured pressure drop in front of the orifice is 10729 mm H2O and measured pressure drop is 400 mm H2O. Pressures are measured at corner taps

Solution: Flow rate is: 155.94 m3/h