The formula to calculate the CFM from differential pressure is:
\[ CFM = 4005 \times \sqrt{dP} \times A \]
Where:
CFM from differential pressure is a measure of the airflow rate calculated based on the differential pressure across a known cross-sectional area. It is commonly used in HVAC systems to determine the airflow through ducts and vents.
For example, if the differential pressure (dP) is 0.5 W.C. and the cross-sectional area (A) is 2 ft², the CFM can be calculated as follows:
\[ CFM = 4005 \times \sqrt{0.5} \times 2 = 4005 \times 0.707 \times 2 \approx 5664.14 \text{ ft³/min} \]
So, the CFM from differential pressure for these values is approximately 5664.14 ft³/min.