This is a pretty straightforward conversion. One cubic foot is equal to 7.48 gallons (US). If you take the reciprocal of that figure (1 / 7.48), you can determine how many cubic feet are in one gallon: 0.134. That is, one gallon is equal to 0.134 cubic feet. So, one gallon per minute equals 0.134 cubic feet per minute. But you're not done, yet. Since there are 60 seconds in a minute, you must divide that figure by 60 to determine how many cubic feet flow in just one second. 0.134/60 = 0.00223 = 2.23E-3 cubic feet per second. That's a pretty small number to work with. It might be more useful to convert that to cubic inches per second (although you didn't ask for the answer in those units). Since a cubic foot is equal to 1728 cubic inches, you can multiply the answer above by that number: 2.23E-3 x 1728 = 3.85 cubic inches per second (in3/s).
1 gallon per minute is about 0.00223 cubic feet per second.
One Imperial gallon of liquid = 277 cubic inches.
1 gallon = 231 cubic inches1 cubic foot = 1,728 cubic inches1 minute = 60 seconds20 gallons per minute = (20 x 231) cubic inches per minute = (20 x 231 / 60) cubic inches per second= (20 x 231 / 60) / 1,728 cubic feet per second= 0.04456 cubic feet per second (rounded)
One US gallon of liquid propane is about 0.133 cubic feet.
1 US liquid gallon = 0.004 cubic meter
cubic feet per second x 60 = cubic feet per minute
Cubic feet per minute x 0.000472 = cubic meters per second.
Multiply cubic feet per second by 60 to get cubic feet per minute.
1 cubic foot = 1,728 cubic inches1 gallon = 231 cubic inches1 gallon = (231/1,728) = 0.13368 cubic foot (rounded)
1 US liquid gallon = 3785.41 cubic centimeters
1 US gallon = 231.000001 cubic inches
1 US gallon = 3.78541178 × 10-12 cubic kilometers