MFL
Member
I’m not sure who needs to know this, but if you need to know the volume of air in your intake/exhaust ducting look no further. Here’s an example with a 6” diameter exhaust duct that’s 25’ long.
Step 1: take the radius of your duct which is half the diameter, 3 in this case and square it (3x3), bringing us to 9”.
Step 2: multiply 9 by 3.14 (pi), 28.27
Step 3: multiply it by the length of your duct, 25 in this case, and you’ll have the cubic inches of 706.85.
step 4: Divide that by 12 to get to feet and you’ll find that the duct holds 58.9 cubic feet of air.
Step 1: take the radius of your duct which is half the diameter, 3 in this case and square it (3x3), bringing us to 9”.
Step 2: multiply 9 by 3.14 (pi), 28.27
Step 3: multiply it by the length of your duct, 25 in this case, and you’ll have the cubic inches of 706.85.
step 4: Divide that by 12 to get to feet and you’ll find that the duct holds 58.9 cubic feet of air.
