# Calculating volume of an air tank given the compressor delivery rate

1. Feb 13, 2012

### dpeff

I have an electric compressor with a delivery rate of 17 SCFM. I would like to calculate the volume of the air tanks that are being charged by keeping track of how long the compressor runs while building air from pressure 1 to pressure 2. I believe that the following calculation is correct. Can someone verify the calculation below which is calculated building air from 0 to 130 PSIG (at sea level)?

Also, if the calculation is basically correct, can the air tank volume be calculated building air from 110 to 130 PSIG?

Given:
Air compressor delivery rate: 17 SCFM
Atmospheric pressure at sea level: 14.7 PSIG
Air tank start pressure: 0 PSIG
Air tank end pressure: 130 PSIG
Air charge time (compressor run time building air from 0 to 130 PSIG): 90 seconds

Calculation of air tank volume:
V1 = 17 SCFM * 90s/60s = 25.5 cubic feet
Since P1V1=P2V2
V2 = (P1/P2)V1
V2 = (14.7)/(130+14.7)25.5
V2 = 2.6 cubic feet