Air Flow Measurement Formula

Cfm duct area sq ft x velocity standard air 70f 29 92 hg mercury 1 cubic foot of standard air 0 075 pounds 13 3 cubic feet of standard air 1 pound.

Air flow measurement formula.

Volume flow is usually measured in cubic feet per minute cfm. Consult factory for your specific condition. The average air velocity is then multiplied by the area of the duct in square feet. Air velocity distance traveled per unit of time is usually expressed in linear feet per minute lfm.

Multiply the flowrate indicated on the meter by the correction factor. By multiplying air velocity by the cross section area of a duct you can determine the air volume flowing past a point in the duct per unit of time. 25 cfm for 1 5 inches 3 8 cm 35 cfm for 2 inches 5 1 cm 48 cfm for 2 5 inches 6 4 cm cfm stands for cubic feet per minute which is how airflow is measured. If you have any questions about this procedure please call your bapi representative.

Pressure temperature compensation flow measurement formula. To calculate the flowrate of a fluid passing through an orifice plate enter the parameters below. Volume flow is usually measured in cubic feet per minute cfm. Normally we do not have an online density measurement.

This correction factor is only accurate within 10. This will equal an approximation of the flowrate of the gas being used. Measure how far in inches the card swings inward to get a sense of the fan s airflow. The answer to this formula is airflow in cfm.

The air flow in cfm is 6 128 ft min air flow in cfm q flow velocity in feet per minute v x duct cross sectional area a air flow in cfm q 3 468 ft min x 1 77 ft 6 128 cfm. This change can be used to measure the flowrate of the fluid. The rough airflow measurements for different inches are. Orifice meters require pressure temperature compensation formula when we use them to measure steam or gas flow in pipes with variable operating pressure and temperature.

Of course there are a host of conditions that must be met in order for the traverse to be accurate. By multiplying air velocity by the cross section area of a duct you can determine the air volume flowing past a point in the duct per unit of time.