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shellback
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I just want the formula that shows how to find for CFM. I have the pipe diameter and the PSI that are available. I'm just using air, nothing special.
shellback said:I just want the formula that shows how to find for CFM. I have the pipe diameter and the PSI that are available. I'm just using air, nothing special.
stewartcs said:Can you be more specific with what you want to know? I presume you mean how to determine the flow rate of air in cubic feet per minute through a pipe when knowing only the pipe diameter and back pressure?
CS
russ_watters said:The pressure is the static pressure in the pipe? That isn't enough to determine the airflow. You need a differential pressure across an orifice, pressure drop in a venturi or velocity pressure from a pitot tube.
The CFM (cubic feet per minute) formula for calculating pipe diameter and PSI (pounds per square inch) is: CFM = (0.00028 * Pipe Diameter) * (PSI / 29.92). This formula assumes that the air is at standard atmospheric conditions (29.92 inches of mercury) and that the pipe is smooth and straight.
To determine the pipe diameter needed for a specific CFM and PSI, you can rearrange the CFM formula to: Pipe Diameter = (CFM * 29.92) / (0.00028 * PSI). Simply plug in the desired CFM and PSI values to calculate the pipe diameter.
Yes, the CFM formula can be used for calculating pipe diameter and PSI for any type of gas or fluid. However, the formula assumes that the air or fluid behaves like an ideal gas and that the pipe is smooth and straight.
The units of measurement for CFM are cubic feet per minute, for pipe diameter are inches, and for PSI are pounds per square inch.
The CFM formula is most accurate for smooth and straight pipes, as it assumes laminar flow. It may not be as accurate for rough or bent pipes, as this can affect the flow of the gas or fluid.