Compressed Air - Storage Volume

The storage volume for a compressed gas can be calculated by using Boyle's Law

p_a V_a = p_c V_c = constant                                                (1)

where

p_a = atmospheric pressure (14.7 psia, 101.325 kPa)

V_a = volume of the gas at atmospheric pressure (cubic feet, m³)

p_c = pressure after compression (psi, kPa)

V_c = volume of gas after compression (cubic feet, m³)

Volume of free gas in a Storage Volume

The amount of free gas at atmospheric pressure in a given volume - like a cylinder storage - can be calculated my modifying (1)

V_a = p_c V_c / p_a                                                     (2)

Gas can be stored in high-pressure cylinders ranging to more than 6000 psig (410 bar). Normal-pressure cylinders are in the range 2000 and 2500 psig (140 and 175 bar) and low-pressure cylinders are in the range 480 psig (34 bar).

Example - Volume of Air in a Cylinder Storage

 Standard atmospheric volume of air compressed in a 1.76 cubic feet K-type cylinder at 2200 psig (2214.7 psia) can be calculated

V_a = (2214.7 psia) (1.76 cu ft) / (14.7 psia)

= 265 (cu ft)

In other words - if air in a 1.76 cubic feet container is compressed to 2200 psig - the same air at atmospheric pressure will occupy 265 cubic feet.  

Temperature ^oC
K
^oF

Length m
km
in
ft
yards
miles
naut miles

Area m²
km²
in²
ft²
miles²
acres

Volume m³
liters
in³
ft³
us gal

Weight kg_f
N
lbf

Velocity m/s
km/h
ft/min
ft/s
mph
knots

Pressure Pa
bar
mm H₂O
kg/cm²
psi
inches H₂O

Flow m³/s
m³/h
US gpm
cfm