How does a liquid ammonia flow meter measure?
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This post was last edited by 654262293 on 2010-12-21 at 11:23. During the delivery of liquid ammonia from our factory, the customers believed that the temperature of the liquid ammonia was too high, and that the readings from the liquid ammonia flow meter were inflated! I would like to ask the experts here: when measuring liquid ammonia, is the flow rate at the actual temperature converted to a flow rate under standard conditions during the measurement process? If not, then what impact does temperature have on flow rate measurement? The design temperature for the liquid ammonia we transport from our plant is 10 degrees Celsius, with a pressure of 2.8 MPa (a). Sometimes, the temperature of the liquid ammonia we transport ranges from 10 to 15 degrees Celsius; at such temperatures, the pressure remains unchanged. What is the deviation between our measured values and the actual values in these cases? Our flowmeter is a mass flowmeter.
At our factory, liquid ammonia for delivery is weighed just like it is with trucks
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Density varies with temperature. All of them can be equipped with a temperature sensor to provide temperature compensation for the mass flow meter.
If a mass flow meter is used for measurement, the signal provided by the meter is a mass value, which is independent of temperature. However, during the measurement process, high temperatures may cause cavitation behind the flow meter, which can affect the measurement. If both parties settle by weighing, this kind of problem will not arise. However, when using a mass flow meter for measurement, it may be necessary for both parties to have an mutually agreed method for verifying the measurement results.
Using a mass flow meter for measurement will solve the problem. Otherwise, the density of liquid ammonia at different temperatures should be known in order to make the calculation.
The main issue is not understanding the principle of mass flow meters